This chapter applies the Chapter 5 alliance flexibility argument to three of America’s most important alliances: NATO, the Taiwan alliance, and the Manila Pact. All three alliance treaties included several types of flexibility language, and across all three alliances the US and others repeatedly used the flexibility language to justify staying out of undesirable conflicts. The only exception is President Johnson’s 1964 decision to intervene in the Vietnam War, motivated by the Manila Pact alliance. However, this chapter demonstrates the exceptionality of this decision. The Manila Pact was designed to be flexible, and the Eisenhower, Kennedy, Nixon, and Ford administrations all used the flexibility language to stay out of conflicts involving Manila Pact signatories including Laos, Pakistan, and South Vietnam. Johnson himself used the flexibility language to keep the US out of the 1965 India–Pakistan War. The chapter discusses why Johnson felt unable to use the flexibility language of the Manila Pact to stay out of the Vietnam War, even though he recognized the existence of such language. This is one of the first discussions of this new irony of the Vietnam War: Johnson knew of an escape route to avoid US involvement, but chose not to use it.