Operation Causeway was a proposed plan by the US military in World War II to land on Taiwan. It would have been a massive high risk, high cost, and high reward operation. In actual history, Causeway was shelved in favor of landing in Luzon.

The Causeway documents are useful not just as an alternate historical reference, but also as a general guide to what a large amphibious invasion of Taiwan would entail (something that, for some mysterious reason, has remained relevant postwar).