The Lawfare Podcast: Wargaming a Chinese Blockade of Taiwan

Date: September 4, 2025
Host: Daniel Byman (Lawfare Foreign Policy Editor)
Guest: Mark Cancian (Senior Advisor, Center for Strategic and International Studies)

Brief Overview

This episode dives into the findings of a major new report from CSIS by Mark Cancian on the prospects and ramifications of a Chinese blockade of Taiwan. The discussion unpacks how such a blockade might unfold, the difference between blockade and invasion, lessons from extensive war gaming, the strategic and legal dilemmas for the US and Taiwan, and how global trade and military alliances would be affected. Particular emphasis is placed on preparation, escalation dynamics, and real-world policy recommendations.

Key Discussion Points & Insights

1. Why Focus on Blockade, Not Invasion?

• Spectrum of Conflict: Conflict can range from "gray area" competition, to blockade, invasion, and nuclear war (03:15).
• Chinese Preparations: Recent PLA exercises encircling Taiwan and missile launches signal likely preparation for blockade, not just invasion (03:50).
• Blockade's Allure & Reality: While blockade seems low risk and low cost for China, war gaming reveals it’s costly and often escalatory. It's not an easy win or a sure prelude to invasion (07:00).

"Very often the costs on a blockade are high. There's a lot of potential for escalation and it's not a good prelude to invasion."
— Mark Cancian (07:13)

2. Core Findings From the Report

Cancian summarizes five major takeaways (04:32):

• Bad Things Can Really Happen: War is possible given rhetoric and military developments.
• Taiwan Alone Cannot Prevail: It puts up a fight but cannot withstand China without US support.
• Ukraine Analogy Fails: Supplying Taiwan like Ukraine is infeasible due to blockade and isolation (05:30).
• US Intervention Is Both Possible & Costly: The US can likely keep Taiwan supplied, but at the cost of hundreds of cargo ships lost in massive convoy battles.
• Preparation Pays Off: Current investments by the US, Taiwan, and Japan reduce risk and bolster deterrence if war comes (06:46).

"Successful intervention is possible. Losses will be very high… but the United States can keep Taiwan supplied."
— Mark Cancian (05:49)

3. How War Games Work and What They Show

• Scope of the Study: 26 war games run, capturing a wide spectrum of escalation and scenarios (08:20).
• Escalation Patterns: Most often, action begets escalation as either side tries to outmaneuver or signal the other (12:48).
• Difficulty of Signaling: Signals often misread; restraint can be interpreted as threat (14:11).

“One side might think it's signaling restraint, while the other side sees a preparation for a larger attack.”
— Mark Cancian (13:49)

4. Impact of Blockade on Taiwan

• Taiwan Alone vs. With US Aid:

  • Without US: Taiwan’s resilience depends on energy; it can hold out for weeks, but not months (11:04).
  • With US: Convoy battles can resupply Taiwan but with massive losses, particularly if the US can operate from Japanese bases (12:00).

• Energy, Not Food, is Critical: Food is less constraining; energy, especially natural gas, is Taiwan’s Achilles' heel (26:56).

5. Legal Ramifications

• China Claims Domestic Policing: Frames blockade as internal; says foreign intervention isn’t justified (15:17).
• US in a Bind: One-China policy complicates legal grounds for action; must emphasize international peace and use of force against an unwilling entity (15:47).

6. Broad Effects: Regional and Global

• Global Economic Disruption: Every country affected, especially due to semiconductor and chip supply (17:10).
• Diplomatic Coalitions: US likely seeks broad diplomatic, not military, support. Many countries might pressure Taiwan to capitulate to restart trade, creating pressure points (17:35).
• Chip Production as Leverage: Prioritizing water and electricity for chips could make Taiwanese chip supply a bargaining chip (18:40).

7. Role of Regional Allies: Japan and the Philippines

• Japan is Critical: US air operations depend on access to Japanese bases—without which, US military options are gravely limited (20:56).
• Philippines’ Limited Role: While helpful, the bases are mostly suited for the South China Sea, and Manila is reluctant to be directly involved over Taiwan (22:03).
• Tension Between US Trade and Security Policy: Current US trade policy strains the alliance with Japan, even as military planning relies on it (23:25).

“On the one hand we say this is absolutely key. On the other hand we are hurting the Japanese with our trade policy, and that tension needs to be resolved.”
— Mark Cancian (23:35)

8. Blockade vs. Invasion: What’s Different?

• Porcupine Strategy Debate: For invasion, a “porcupine” Taiwan with missiles and mines is favored. For blockade relief, traditional forces (planes/ships) are more useful to escort convoys (24:13).
• Strategic Balance: Moving entirely to an asymmetric “porcupine” model may undermine blockade-breaking ability (25:30).

9. Recommendations to Taiwan

• Energy Resilience: Maintain reserves, reconsider shuttering nuclear plants, prioritize direct transition to renewables vs. natural gas (26:56).
• Merchant Shipping: Secure access to reserve/“blockade runner” ships—possibly via Japan as a transshipment hub (29:47).
• Electrical Grid Hardening: Anticipate and prepare for attacks on infrastructure to speed recovery (31:14).

“As they move towards this green energy initiative, their ability to resist declines substantially. ... Our recommendation is keep [the nuclear plant] going and to move directly to renewables.”
— Mark Cancian (28:24)

10. Recommendations to the United States

• Expand Reserve Shipping Fleet: Especially with natural gas carriers (32:03).
• Navy Convoy Skills: Rebuild expertise in protecting and escorting convoys under threat.
• Harden Pacific Bases: Build hardened shelters at bases like Kadena to limit aircraft losses in missile strikes (33:05).

11. Negotiated "Off Ramps" & Escalation Dangers

• No Total Victory Likely: Crisis likely ends with a negotiated solution, so planning options for de-escalation in advance is essential (34:25).
• Avoid Humiliation, Preserve Interests: Need solutions that let China de-escalate without appearing humiliated, while not conceding vital US/Taiwanese interests.
• Study Options Without Hand-Tipping: Develop “off ramp” proposals in think tanks and studies to retain deniability and flexibility (36:11).

“If we're looking at compromises that do give up vital interests for Taiwan, then yes, that's going to be a vulnerability. But if we're doing this intellectual work ... then they would be deniable to the Chinese, but it is a tension.”
— Mark Cancian (36:11)

Notable Quotes & Memorable Moments

• On the inevitability of conflict:
  “If we heard that tomorrow the Chinese were preparing a conflict with Taiwan, no one would ... say, ‘Wow, didn’t see that coming.’ No, everybody would say, we’ve been talking about that for years.” (Mark Cancian, 04:40)
• On Taiwan's military needs:
  “In the blockade scenarios ... it is useful having Taiwan be able to field jet aircraft and ships because they help escort convoys and bring in ... this economic lifeline.” (Mark Cancian, 25:19)
• On miscommunication and escalation:
  “Signals needed to be accompanied by something verbal, some explanation ... they were not enough on their own to be understood.” (Mark Cancian, 14:24)

Important Segments with Timestamps

• 02:34: The episode's opening assertion: a Taiwan conflict affects the entire world economy.
• 04:32: Cancian’s five major takeaways from the report.
• 07:57: Explanation of war games methodology.
• 12:48: How escalation occurs in a blockade scenario.
• 14:11: The danger of misinterpreted signals.
• 15:17: Overview of legal complexities for the US and China.
• 17:10: Global economic and trade impacts.
• 20:56: Why Japan is militarily indispensable for the US.
• 24:13: The porcupine strategy debate for Taiwan’s military.
• 26:56: Taiwan’s critical vulnerability: energy dependence.
• 32:03: US recommendations: expand shipping and harden bases.
• 34:25: The inevitability and structure of negotiated off ramps.

Conclusion

This episode offers a thorough and sober look at a potential Chinese blockade of Taiwan, drawing from extensive war gaming. It details the escalation dangers, critical vulnerabilities (especially energy), the need for stronger alliances, especially with Japan, and both legal and military dilemmas for US policymakers. The conversation is forward-looking, recommending urgent prep steps for both Taiwan and the US while warning of significant costs, global disruptions, and the crucial need for both resilience and diplomatic flexibility in the event of war.