The recent development of missile forces of People's Liberation Army (PLA) is claimed to gradually keep the U.S. intervention in Cross-Strait conflicts at bay. Nonetheless, this claim is an exaggeration. Ballistic missiles are fast and thus hard to intercept, but are expensive and inaccurate. In contrast, cruise missiles are inexpensive and accurate, but are slow and thus easy to intercept. Both are constrained by their inherent character as an expendable weapon. The longer the range, the higher the price; thus, the fewer the number, the less likely it is that the missiles can project destructive power towards targets, unless they are nuclear-armed. Furthermore, given that the cost increases with range, medium or intermediate range missiles are bound to be excessively expensive, and they are unlikely to neutralize the U.S. missile defense system. As a result, except China's immediate regions (such as Taiwan or U.S. forward deployments in East Asia), the PLA missile forces alone cannot pose a threat to the U.S. aircraft carriers or military bases in Guam. The implications of missile threats are rather political: to test the U.S. resolution to defend Taiwan.