Taiwan invasion sparks regional proliferation

Five years ago — and certainly a decade ago — coercive annexation of Taiwan by the People’s Republic of China (PRC) might have seemed an extreme scenario. Unfortunately, this is no longer the case. The rising crescendo of PRC air and maritime pressure operations near the island, missile firings, and so on are bringing Beijing within a few steps of the maritime quarantine or similar operations that would likely be central to an attempt at coercive annexation.

Meanwhile, China’s meteoric military buildup across the board gravely threatens other nations. Backstopping it all is a major nuclear weapons ramp-up, the latest elements of which are detailed here to the very cutting-edge of public information, much of it from the Pentagon’s just-released 2023 “China Military Power Report”.[1] Based on this information, we conclude that if the PRC succeeded in coercively annexing Taiwan, repercussions could include nuclear proliferation with regional — and even global — security consequences.

Even under a baseline scenario, a nuclear proliferation cascade following a PRC-coerced annexation of Taiwan could see hundreds of nuclear warheads added to stockpiles globally. More dire cases — for example, in which Japan and/or South Korea nuclearized extensively, China responded, and the U.S. and Russia then each expanded their nuclear forces — could trigger a chain of proliferation that ultimately adds a thousand or more warheads to nuclear stockpiles globally. The addition of such warhead numbers, plus the entry of new nuclear powers with no nuclear command, control, or operations experience in the midst of a tense geopolitical environment, would be a recipe for instability. The risks that could result if these nuclear proliferation whirlwinds are unleashed should drive the U.S. to redouble its efforts to ensure that this Pandora’s box is never opened.

How Would Coercive Annexation of Taiwan by the PRC Be Different Than Prior Crises?

Over six decades, the U.S. nuclear umbrella over key Asian allies has weathered multiple stress tests. These include China’s 1964 nuclear test, U.S. normalization of relations with the PRC in 1972, the loss of the Vietnam War a year later, President Jimmy Carter’s 1976 campaign pledge to withdraw ground troops from the Korean Peninsula, nuclear weapons development and deployment by India and Pakistan, and North Korea’s acquisition of nuclear weapons.[2] These prior disruptions shook the region’s confidence in American security guarantees — and helped motivate South Korea and Taiwan to pursue secret nuclear weapons programs in the 1970s and 1980s that were later shuttered under U.S. pressure — but they did not shake the structure to its foundation.[3]

American economic, technological, and military excellence kept U.S. power credible and granted the leverage needed to dissuade key East Asian states that were not nuclear as of 1965 from going nuclear (with the exception of North Korea). Washington was able to offer the “carrot” of coverage by a first-rate nuclear umbrella while wielding the “stick” of economic, technological, and hard security exclusion against countries that insisted on pursuing nuclear weapons capability. Furthermore, prior revisionists of the security order (such as North Vietnam and North Korea) were both small-to-medium powers whose actions unsettled the regional order but did not fundamentally call American alliance commitments into question. South Vietnam was not a U.S. treaty ally, and the U.S. led allied efforts to defend South Korea during the Korean War, boosting its credibility.

If the PRC coercively annexed Taiwan, by contrast, proliferation pressures would likely be the highest East Asia has seen in decades. At this point, only a coalition of states that includes the U.S. can credibly balance China in the conventional military realm. In the nuclear arena, none of China’s East Asian neighbors can fully deter, much less balance, its power; North Korea is beholden to Beijing in critical respects, and the rest lack nuclear weapons. Both Japan and South Korea either possess (or are acquiring) formidable long-range conventional strike assets. Yet these would likely be insufficient to mitigate PRC nuclear coercion because they could not credibly threaten China’s national leadership, critical infrastructure, and nuclear weapons complex to a degree proportionate to the threat of PRC conventional strike weapons (and their nuclear counterparts) to the Japanese and Korean homelands.

The cases of India and Pakistan offer relevant historical examples of how countries may respond to nuclear threats that lack a credible external counterbalance. The U.S. engaged with both countries (and in the case of Pakistan, offered substantial but circumscribed security support) but did not have alliance relationships or provide other security guarantees. This meant the U.S. ultimately failed to dissuade them either from acquiring or deploying nuclear weapons. Survivalist security concerns carried the day, with Pakistani President Zulfiqar Ali Bhutto famously declaring in 1965 that “if India builds the bomb, we will eat grass or leaves, even go hungry, but we will get one of our own.”[4]

China’s East Asian neighbors are not currently locked into maximal rivalry with Beijing. But the South Asian example reflects the lengths to which nations will go if nuclear weapons acquisition comes to be seen as a survival imperative necessary to ensure national sovereignty in a world where they have concluded they are increasingly on their own.

Reinforcing that point: A successful coercive annexation of Taiwan would also leave PRC military forces mostly intact — and thus available as a credible coercive instrument. This, in turn, would give Beijing enormous leverage in Asia and beyond. Gains on Taiwan might even arouse the PRC’s temptations to further expand its land territory by force, or use a combination of island conquests, feature construction (“island building”), and a much more aggressive military presence to effectively implement its own version of the Monroe Doctrine across maritime Asia.[5]

Such a chain of events could very plausibly trigger a crisis of confidence in the strength of Washington’s commitment to use conventional or nuclear force in defense of a regional ally. After all, if the U.S. would not (or could not) deploy sufficient conventional military power (implicitly or explicitly backed by nuclear arms) to keep a quasi-ally and very strategically important society like Taiwan free, would American allies later be as willing to assume that Washington would risk Los Angeles or Seattle for Tokyo, Seoul, or the Senkaku Islands (uninhabited lands that are administered by Japan) to meet alliance obligations?[6]

Of course, it is not possible to answer that question conclusively until such a challenge concretely presents itself. But if evolving circumstances compelled allies ostensibly under the U.S. nuclear umbrella to ask such questions, the very act of asking begins to pencil in an answer along the lines of “perhaps not.” Viewing nuclear weapons acquisition as a national necessity might not be far behind — either in the form of a sharing arrangement, in which U.S. “forward-based” weapons are delivered by host country aircraft, or else through the development of a sovereign nuclear deterrent.[7]