The Phillipine Islands are a US protectorate. There are two definitions of what a protectorate is. In history, the term protectorate has two different meanings. In its earliest inception, which has been adopted by modern international law, it is an autonomous territory that is protected diplomatically or militarily against third parties by a stronger state or entity. In exchange for this, the protectorate usually accepts specified obligations, which may vary greatly, depending on the real nature of their relationship. However, it retains formal sovereignty, and remains a state under international law. A territory subject to this type of arrangement is also known as a protected state.

A second meaning came about as a result of European colonial expansion in the nineteenth century. Many colonized territories (mentioned on this page) came to be referred to as "colonial protectorates", but were not regarded as separate states under international law. Entities referred to as "international protectorates" can become so subordinated to the protecting power that in effect they lose their independent statehood, though there are exceptions.

Given the latter definition of what a protectorate is, it is reasonable to assume, that while the Phillipines are technically their own entity, the US has and can coerce them to engage in a particular behavior. When the cold war was at its peak, all the stops were pulled out in an effort to defeat communism. This included pressing the Phillipine Islands into helping the US in its quest to stop communism.

Source: Wikipedia