Operation Causeway: The Forgotten U.S. Military Plan to Invade Taiwan

Operation Causeway, Explained: Given Beijing's hardline stance on the status of the self-ruling island of Taiwan, it is almost certain that the People's Liberation Army has drawn up numerous invasion plans. The Chinese Communist Party, which has never actually ruled over the island, maintains that it is a breakaway province that will be brought back to mainland control.

Currently, only 13 countries (plus the Vatican) recognize Taiwan as a sovereign country.

Despite the fact that the PLA dwarfs Taiwan's armed forces, such an invasion would likely be hard fought and highly costly. The forces from the People's Republic of China would have to cross the roughly 100-mile-wide Taiwan Straits and make a landing on what would likely be well-defended beaches. It is generally expected that the People's Liberation Army Navy (PLAN) would take heavy losses before even reaching the island – and the situation wouldn't be much better once a beachhead was established, if there were even possible.

The island is well-suited to the defender, a fact that Imperial Japan learned the hard way, even after it was granted the island as part of the settlement with the Chinese Qing Dynasty after the Sino-Japanese War (1894-95). Under the Treaty of Shimonoseki, signed on April 17, 1895, Taiwan and P'eng-hu Islands were ceded to Japan in perpetuity. The Taiwanese soon revolted, declaring the Taiwan Republic, and Japan was forced to crush that first nationalist movement.

More than a dozen bloody uprisings continued over the next two decades, but the most famous – the Wushe Incident – occurred in 1930 in the primarily aboriginal region of Musha and involved the aboriginal tribes, who practiced ritual headhunting. That rebellion lasted some 50 days and cost thousands of lives.

U.S. Planned Invasion: Operation Causeway

It was during the Second World War that the U.S. military also considered an invasion of Taiwan or Formosa, as the island was known under Japanese control. The plan, dubbed Operation Causeway, was to invade the island and then use it as a launching pad for an invasion of the Japanese home islands.

The planners saw that Formosa would have provided a suitable base for the strategic bombing campaign against Japan as well. In addition, its planned capture was meant as a symbolic demonstration of American support for the continued participation of China in the war. In addition, Taiwan provided food to supply the Japanese troops, while it also provided important ports and airfields, which allowed the Japanese to strike targets all around East Asia. There was also the feeling among some in the U.S. military that the Formosans (Taiwanese) were too supportive of the Japanese war effort, as thousands of volunteers also served in the Japanese military.

Operation Causeway's biggest supporter was Admiral Ernest J. King, Chief of Naval Operations, but opposing it was General Douglas MacArthur, commander-in-chief of the South West Pacific Area, who pushed for the invasion of Luzon in the Philippines instead.

Admiral Raymond Spruance, commanding the Fifth Fleet, concurred with MacArthur and called for the capture of Iwo Jima and Okinawa. The latter provided the same staging area for an invasion of the Japanese home island while also serving as a suitable base for bombers. It was also significantly smaller than Formosa and didn't require as sizeable of an invasion force.

In fact, the U.S. War Department had estimated that to invade and hold Formosa would have required upwards of half a million men – especially as the loyalty of the population to Japan still remained in question. As the fighting would have then taken place in the island's mountains and jungles, as well as in its urban centers, it was expected that American casualties could have topped 150,000.

It was simply not worth the risk, and the island was bypassed. With the support of President Franklin Roosevelt, MacArthur's plan for the invasion of Luzon and Spruance's proposals to invade Iwo Jima and Okinawa were put into operation.

Should Beijing ever decide it were actually to invade, the question would be whether it would be worth the effort. The PLA could expect to face far more significant obstacles than the Americans 80 years ago, and Beijing's forces aren't likely to be welcomed as liberators.

Such a campaign would likely destroy the nation and require millions of men to subdue the island. That would ruin its value to the mainland – and it would instead result in a 21st-century version of making a desert and calling it peace.

About the Author

A Senior Editor for 1945, Peter Suciu is a Michigan-based writer who has contributed to more than four dozen magazines, newspapers and websites. He regularly writes about military hardware, firearms history, cybersecurity and international affairs. Peter is also a Contributing Writer for Forbes. You can follow him on Twitter: @PeterSuciu. 

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