This has been par for the course for decades. They used to be on good terms with Saddam Hussein, Gaddafi, Iran after they couped Mossadegh. Heck, they even armed and trained Osama Bin Laden to fight the soviets in Afghanistan. It has always been a deadly gambit to ally yourself with the United States.
I'm not saying it's universally the case of course. For every Saddam there's a Pinochet, for every Gaddafi there's a Suharto. But the fact that the US can drop an ally just like that should not be a surprise to anyone.