Review Reports

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

I have read the article and have a few suggestions for the authors.
1. The introduction lacks sufficient details about the current context and necessity of the chosen study. Additionally, the introduction should include references from the literature to support the statements made. 
2. Why were the years 2010, 2016, and 2020 selected? What is their significance? I suggest the authors provide references explaining why these years were chosen. 
3. The discussion section should contain lines 67-84, not the introduction. The introduction should present the research questions that the authors will address through their study, explain the article's novelty, and present the working hypotheses.
4. What is the place of Ais on line 340 in the mathematical equations? What about 1_jNin? I suggest that the authors review the mathematical formulas and provide references for them from the literature.
5. The presentation of the findings and discussions is superficial. The authors do not present the data from the analysis. Furthermore, certain tables and results are presented in the appendix but are not referred to in the article. 
6. The references section contains few works from specialized literature related to the study. I suggest that the authors supplement this section with recent works from mainstream international publications.

Author Response

Comment 1: The introduction lacks sufficient details about the current context and necessity of the chosen study. Additionally, the introduction should include references from the literature to support the statements made. 

Response 1: We have revised the Introduction to foreground the policy context (2014 export ban; tightening in 2020), motivate why the regime matters for structural transformation, and then position the economic mechanisms as the analytical lens. See Section 1 (Introduction). We have also include references from the literature to support the statements made.

Comment 2: Why were the years 2010, 2016, and 2020 selected? What is their significance? I suggest the authors provide references explaining why these years were chosen. 

Response 2: We have added explicit justification for benchmark years based on availability of official IO tables and their alignment with key policy and investment phases (2010 pre-ban baseline; 2016 early downstreaming benchmark; 2020 accelerated processing investment). The IO 2020 is currently the latest version of Indonesia IO table, which was published in 2025. See Section 1 and Section 3.1.

Comment 3: The discussion section should contain lines 67-84, not the introduction. The introduction should present the research questions that the authors will address through their study, explain the article's novelty, and present the working hypotheses.

Response 3: We streamlined the Introduction by moving interpretive discussion language into Section 4 (Results and Discussion) and Section 5 (Policy Implications). The Introduction now focuses on context, motivation, questions, and contribution. We also clarified research questions and contributions in the Introduction and provided a brief preview of main patterns (structural narrowing, reorientation of multipliers to EV-adjacent sectors, declining labor multipliers). See end of Section 1.

Comment 4: What is the place of Ais on line 340 in the mathematical equations? What about 1_jNin? I suggest that the authors review the mathematical formulas and provide references for them from the literature.

Response 4: Corrected notation (A is the input coefficient matrix; 1(·) indicator function; l_{jN} Leontief-inverse elements), added definitions directly in the Methods text, and replaced empty equation placeholders with readable equation lines (1)–(6). See Section 3.4–3.6.

Comment 5: The presentation of the findings and discussions is superficial. The authors do not present the data from the analysis. Furthermore, certain tables and results are presented in the appendix but are not referred to in the article. 

Response 5: We have edited and rewrite some parts of Chapter 4 to strengthen the discussion. We also added a summary table in the Results section (Table 1) to report headline linkage and labor-multiplier indicators and added explicit references to Appendix Tables A1–A3 in the main text. See Section 4.1 and related notes..

Comment 6: The references section contains few works from specialized literature related to the study. I suggest that the authors supplement this section with recent works from mainstream international publications.

Response 6: Thank you for the suggestion. We have edited Chapter 1 and 2 to include some recent works from the references section. Also, we improved the references with few more recent studies related to our research, and included some of their insights to the Chapter 1 and 2 as well.

 

Reviewer 2 Report

Comments and Suggestions for Authors

Suggestions to Authors

1. Can the authors include newer references
2. Can the authors include figures and tables
3. Sections 2.3 and 2.4 can they be written in continuous form 
4. Can all the equations be numbered
5. Sections 5.3-5.6 can the authors write in continuous form

Author Response

Comment 1: Can the authors include newer references

Response 1: We have added 9 more references and they are all relatively new studies related to our topic.

Comment 2: Can the authors include figures and tables

Response 2: We added table and figure to the article and some others already available in the appendix.

Comment 3: Sections 2.3 and 2.4 can they be written in continuous form 

Response 3: Thank you for the input. We have re-write the sections.

Comment 4: Can all the equations be numbered

Response 4: Thank you we have edited all and put number to each formula.

Comment 5: Sections 5.3-5.6 can the authors write in continuous form

Response 5: Thank you, we have edited as your input.

Reviewer 3 Report

Comments and Suggestions for Authors

This manuscript presents a careful and technically sound multisectoral input–output analysis of Indonesia’s nickel downstreaming strategy across three benchmark years (2010, 2016, 2020). The empirical approach is well executed, transparently explained and appropriate for the descriptive aims of the study. The integration of linkage analysis with output and labour multipliers is a clear strength, and the paper succeeds in documenting how nickel’s domestic economic footprint has evolved during the downstreaming period.

That said, despite the solidity of the empirical work, the manuscript in its current form is not yet ready for publication. The principal limitation is not methodological, but conceptual and scholarly positioning. In particular, the paper is insufficiently embedded in the rapidly expanding literature on critical minerals, downstreaming and EV-related industrial policy that has emerged since 2022. As a result, the contribution appears narrower and more dated than it needs to be, given the quality of the underlying analysis.

The most significant issue concerns the literature review and framing. The manuscript cites very little work published after 2022, despite the fact that Indonesia’s nickel downstreaming strategy has become one of the most intensively studied and debated cases in the global critical minerals literature over the past several years. Since 2022, there has been a substantial expansion of scholarship addressing critical mineral industrial policy, EV and battery supply chains, resource nationalism, geopolitical fragmentation, export controls, labour and distributional outcomes, and the environmental and energy-system constraints associated with capital-intensive processing.

In its current form, the paper reads as if it is intervening primarily in a pre-2022 debate (notwithstanding the last benchmarking year of 2020), even though its policy relevance is clearly contemporary and its empirical period extends into the heart of the downstreaming push. This disconnect weakens the paper’s impact and risks underestimating how crowded and fast-moving the current literature has become. The literature review would benefit from a substantive update that explicitly engages with post-2022 contributions and clarifies how this paper speaks to, confirms, refines, or, indeed, complicates recent arguments.

Relatedly, the manuscript would benefit from sharper articulation of its contribution relative to recent work. Several of the paper’s core findings (that downstreaming tends to promote capital deepening rather than broad employment growth, that domestic spillovers concentrate in a narrower set of complementary sectors, and that labour intensity declines as value added rises) are increasingly recognised in recent studies of critical minerals and industrial policy.

This does not diminish the value of the paper, but it does require clearer positioning. The author(s) could clarify whether the contribution lies in providing the first systematic IO-based structural mapping of Indonesia’s nickel economy across multiple benchmark years, in offering new empirical evidence on labour multipliers that has been missing from prior debates, or in revealing a specific mechanism of “structural narrowing” that helps explain why downstreaming delivers uneven developmental outcomes. Making this explicit would strengthen the manuscript’s originality and relevance.

While the national focus on Indonesia is appropriate, the analysis would be strengthened by more explicitly situating the case within broader global dynamics. Indonesia’s nickel downstreaming strategy is deeply embedded in global EV and battery value chains, geopolitical competition over critical minerals, trade disputes related to export restrictions, and mounting energy and decarbonisation constraints. These dynamics are increasingly central to how downstreaming is interpreted in the literature.

The paper does not need new data to address this point, but it would benefit from tighter integration of these themes in the Introduction, Literature Review, and Discussion, drawing on recent scholarship to frame Indonesia not just as a national case, but as a structurally important node in an evolving global critical-mineral system.

Finally, there are some minor issues that could be addressed in revision. The Conclusion contains residual placeholder phrasing that needs polishing. There is some repetition between the Results and Policy Implications sections, particularly regarding labour intensity and capital deepening, which could be tightened for concision. These are secondary concerns that are straightforward to resolve once the larger framing issues are addressed.

Author Response

Comment 1: Although the empirical work is solid, the manuscript is not yet ready for publication. The main limitation is conceptual rather than methodological. It is insufficiently positioned within the rapidly expanding post-2022 literature on critical minerals, downstreaming, and EV-related industrial policy, which makes the contribution appear narrower and more dated than the strength of the analysis warrants.

Response 1: 

We sincerely thank the reviewer for this insightful observation. We appreciate the recognition of the solidity of the empirical analysis. We agree that the original manuscript did not sufficiently situate the study within the rapidly evolving post-2022 literature on critical minerals, downstreaming strategies, and EV-related industrial policy.

In the revised version, we have substantially strengthened the conceptual framing and scholarly positioning of the paper. Specifically, we have:

1. Expanded the literature review to incorporate recent contributions (2022–2025) on critical mineral geopolitics, industrial policy design, and battery supply-chain restructuring.
2. Clarified how Indonesia’s nickel downstreaming strategy relates to current debates on strategic autonomy, green industrial policy, and global supply-chain realignment.
3. More explicitly articulated the paper’s contribution relative to emerging EV and battery-industrialization frameworks.

These revisions reposition the manuscript within the contemporary policy and academic debate and clarify its broader relevance beyond the specific empirical case.

We hope the revised manuscript now better reflects the significance and timeliness of the analysis.

Comment 2: The main issue lies in the literature review and framing. The manuscript includes limited post-2022 scholarship, despite Indonesia’s nickel downstreaming strategy becoming a central case in the global critical minerals debate. Since 2022, research has expanded significantly on critical mineral industrial policy, EV and battery supply chains, resource nationalism, geopolitical fragmentation, export controls, distributional effects, and environmental and energy constraints linked to capital-intensive processing.

Response 2: 

We agree that the original manuscript did not sufficiently engage with the rapidly expanding post-2022 literature on critical minerals and industrial policy.

In the revised version, we have substantially updated and expanded the literature review to incorporate recent scholarship on EV and battery supply chains, resource nationalism, geopolitical fragmentation, export controls, distributional outcomes, and environmental and energy-system constraints associated with downstream processing. We have also clarified how Indonesia’s nickel downstreaming strategy fits within these broader contemporary debates.

These revisions strengthen the conceptual framing and ensure that the manuscript is more clearly positioned within the current state of the literature.

Comment 3: This does not diminish the paper’s value, but clearer positioning is needed. The authors should specify whether the contribution lies in providing the first systematic IO-based mapping of Indonesia’s nickel economy, offering new evidence on labour multipliers, or identifying a mechanism of “structural narrowing” that explains uneven downstreaming outcomes. Clarifying this would strengthen the manuscript’s originality and relevance.

Response 3: 

In the revised version, we have clarified that the paper makes three interrelated contributions: (1) it provides a systematic input–output–based structural mapping of Indonesia’s nickel economy across multiple benchmark years; (2) it introduces new empirical evidence on labour multipliers that has been underexplored in prior debates; and (3) it identifies a mechanism of “structural narrowing” that helps explain the uneven developmental effects of downstreaming.

By making these contributions more explicit in the introduction and conclusion, we believe the manuscript’s originality and relevance are now more clearly conveyed.

Comment 4: Finally, there are minor issues to address in revision. The conclusion contains placeholder language that requires polishing, and there is some repetition between the Results and Policy Implications sections, particularly on labour intensity and capital deepening. These are secondary and can be resolved once the broader framing issues are addressed.

Response 4: We thank the reviewer for these helpful suggestions. In the revised manuscript, we have carefully edited the Conclusion to remove residual placeholder language and improve clarity. We have also streamlined the discussion to reduce repetition between the Results and Policy Implications sections, particularly regarding labour intensity and capital deepening. These revisions enhance concision and overall coherence.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Accept in the present form

Author Response

Comment 1: Accept in the present form.

Response 1: Thank you for your thoughtful review and constructive feedback. We truly appreciate your time and guidance, which greatly improved the quality of our manuscript. We are sincerely grateful for your support and recommendation for acceptance.

Reviewer 3 Report

Comments and Suggestions for Authors

Thank you for the opportunity to review this revised manuscript. The paper has improved substantially compared to the original submission. In particular, the conceptual framing has been strengthened and the manuscript is now more clearly positioned within the rapidly expanding post-2022 literature. The explicit articulation of the paper’s contributions, especially the mechanism of “structural narrowing” and the integration of labour multipliers, significantly enhance the manuscript’s relevance and timeliness.

That said, several issues remain before the manuscript is fully ready for publication.

First, Figure 1 should be reconsidered. It is not clearly integrated into the argument, is not adequately discussed in the text, and contains presentation issues (including a spelling error and ambiguous export trends). More importantly, the paper explicitly shifts focus away from trade/export indicators toward domestic production structure; the inclusion of this figure risks diluting that analytical move. I recommend removing the figure unless it is substantially revised and more clearly linked to the structural analysis (and referenced in the text).

Second, the manuscript would benefit from tightening. There is noticeable repetition between the Results, Policy Implications, and Conclusion sections, particularly regarding labour intensity, capital deepening and EV-adjacent sector formation. Streamlining these sections would improve clarity and reduce redundancy.

Third, the literature review structure could be slightly reorganised for coherence. Some subsections overlap conceptually, and the placement of “Data” within Section 2 is confusing. A clearer separation between literature review, contribution and methods would improve readability.

Finally, I encourage moderation of any “first-ever” claims unless they can be unequivocally substantiated. Framing the contribution as “one of the first” or “among the first” longitudinal IO-based mappings may reduce unnecessary reviewer scrutiny.

With the revisions outlined above, I would consider the paper suitable for publication.

Author Response

Comment 1: The revised manuscript has improved substantially — the conceptual framing, positioning within post-2022 literature, and the articulation of contributions (especially "structural narrowing" and labour multipliers) are now strong.

Response 1: Thank you for recognising the improvements made to the manuscript. We invested considerable effort in strengthening the conceptual framing and positioning the paper more clearly within the post-2022 literature. We are glad that the articulation of our key contributions, particularly the mechanism of "structural narrowing" and the integration of labour multipliers, is now relevant and timely.

Comment 2: Figure 1: Remove or substantially revise it. It's poorly integrated into the argument, contains errors (including a spelling mistake), and conflicts with the paper's stated shift away from trade/export indicators toward domestic production structure.

Response 2: We agree with the reviewer's assessment. Upon reflection, Figure 1 was not sufficiently integrated into the core argument and risked diluting the paper's analytical focus on domestic production structure. We have therefore decided to remove the figure entirely from the revised manuscript. We believe this change strengthens the coherence of the paper. Thank you.

Comment 3: Repetition across sections: The Results, Policy Implications, and Conclusion sections overlap considerably on topics like labour intensity, capital deepening, and EV-adjacent sector formation. These need to be streamlined.

Response 3: 

We agree that the original manuscript contained unnecessary repetition across the Results, Policy Implications, and Conclusion sections. We have now streamlined these sections as follows:

-) Section 4 (Results) serves as the sole location for detailed empirical findings, including the specific labour multiplier figures, the full enumeration of EV-adjacent sectors, and the explanation of capital deepening mechanisms.
-) Section 5 (Policy Implications) now references findings from Section 4 through cross-references rather than restating them, allowing the discussion to focus on policy prescriptions.
-) Section 6 (Conclusion) has been substantially shortened. The original version restated all three main findings twice — first in a summary paragraph, then again in expanded form. The second, longer restatement has been removed entirely.

Additionally, policy-oriented content on skills, human capital, and worker mobility that previously appeared in both Section 4 and Section 5 has been consolidated in Section 5 alone. We believe these changes significantly improve the clarity and flow of the manuscript.

Comment 4: Literature review structure: Some subsections overlap conceptually, and placing "Data" within Section 2 is confusing. Literature review, contribution, and methods should be more clearly separated.

Response 4: 

We agree with this observation and have restructured Section 2 accordingly. Three changes were made:

First, Section 2.1 was renamed from “Data” to “Critical Minerals and Resource-Based Industrialization in Energy Transition,” which accurately reflects its content. The actual data description remains in Section 3.1.

Second, Section 2.5 (Contribution) was trimmed from five paragraphs to two, retaining only the core contribution statement and a brief methodological positioning paragraph. Three paragraphs of contextual literature on the global EV value chain, complementary capabilities, and post-2022 policy proliferation were removed from 2.5, as they did not belong in a contribution section.

Third, Section 2.6 (Recent Debates and Global Context) was revised to absorb the relocated material from Section 2.5, integrating it into existing paragraphs rather than simply appending it. This eliminated the overlap that previously existed between Sections 2.5 and 2.6 on topics such as EV industry dynamics, geopolitical concerns, and energy and environmental governance. The relevant citations (Brutschin et al. 2023; IEA 2023; CREA & CELIOS 2024; Solidar Suisse 2024; LPEM UI & NRGI 2025; OECD 2023; IEA 2024; WTO 2022; USITC 2024) have been retained and are now placed in their appropriate context within Section 2.6.

Additionally, the novelty claim in Section 2.5 was moderated from “the first” to “one of the first,” in response to a related reviewer comment. We believe these revisions establish a clearer separation between literature review, contribution, and methods.

Comment 5: Tone of novelty claims: Soften any "first-ever" language to something like "one of the first" or "among the first" to avoid drawing unnecessary scrutiny

Response 5: We agree with this suggestion. The language in Section 2.5 has been revised from “the first longitudinal, sector-resolved analysis” to “one of the first longitudinal, sector-resolved analyses.” We have also reviewed the rest of the manuscript to ensure that no other unqualified novelty claims remain.

Comment 6: Literature review structure: Some subsections overlap conceptually, and placing "Data" within Section 2 is confusing. Literature review, contribution, and methods should be more clearly separated.

Response 6: 

We agree with this observation and have restructured Section 2 accordingly. Three changes were made:

First, Section 2.1 was renamed from “Data” to “Critical Minerals and Resource-Based Industrialization in Energy Transition,” which accurately reflects its content. The actual data description remains in Section 3.1.

Second, Section 2.5 (Contribution) was trimmed from five paragraphs to two, retaining only the core contribution statement and a brief methodological positioning paragraph. Three paragraphs of contextual literature on the global EV value chain, complementary capabilities, and post-2022 policy proliferation were removed from 2.5, as they did not belong in a contribution section.

Third, Section 2.6 (Recent Debates and Global Context) was revised to absorb the relocated material from Section 2.5, integrating it into existing paragraphs rather than simply appending it. This eliminated the overlap that previously existed between Sections 2.5 and 2.6 on topics such as EV industry dynamics, geopolitical concerns, and energy and environmental governance. The relevant citations (Brutschin et al. 2023; IEA 2023; CREA & CELIOS 2024; Solidar Suisse 2024; LPEM UI & NRGI 2025; OECD 2023; IEA 2024; WTO 2022; USITC 2024) have been retained and are now placed in their appropriate context within Section 2.6.

Additionally, the novelty claim in Section 2.5 was moderated from “the first” to “one of the first,” in response to a related reviewer comment. We believe these revisions establish a clearer separation between literature review, contribution, and methods.

Author Response File: Author Response.pdf