The countries do have quite a lot of 'say' in it. S. Korea, Japan and Germany are not vassal states. Neither is Egypt, Israel or Saudi Arabia. It's different

The countries do have quite a lot of 'say' in it. S. Korea, Japan and Germany are not vassal states. Neither is Egypt, Israel or Saudi Arabia. It's different in every case, and there's a lot of factors, but mostly it's for mutual benefit. The Japanese and German elite are very happy to have the Americans there because it serves as a buffer. It's probably more complicated in Egypt, but the military is one of the only civic institutions with integrity, the citizens actually know that, and that it's because they are backed/supported by the US. Even on the 'Arab Street' they have an instinct for what that balance means even if it's obviously more difficult for some. But if Egypt really wanted the US to leave they could make them leave. Same in most places.