Taiwanese may be able to partially answer that question today. The Obama Administration announced that it will not sell Taiwan the 66 new F-16 C/D fighter planes requested by that government. Instead, the United States will only agree to upgrade Taiwan's existing fleet of F-16 A/B aircraft.
The decision, apparently intended to mollify China, drew instant bipartisan criticism. Texas Republican Senator John Cornyn, in whose state Lockheed Martin would have built the Taiwanese jets, called the move a "slap in the face of an ally." Even Obama partisan Howard Berman of California, the ranking Democrat on the House Foreign Affairs Committee, called it a "half measure."
Half a measure was not better than none as far as China was concerned. The U.S. action intended to defer to Chinese diplomatic sensitivities was instead met with an angry denunciation by Beijing. The pressure from China for a complete U.S. abandonment of the Taiwanese government continues unabated.
Understandably, U.S. allies, including Israel, watch and wonder. Are their fears overblown? Well, have you ever heard of the Shah of Iran? Or a former Egyptian dictator named Hosni Mubarak? Or a country called the Republic of Vietnam, more commonly known as South Vietnam? They also were allies of the United States, until the United States abandoned them. Who's next?