Mostly, after WWI, Britain promised them their current stretch of land in the Middle East. While Britain did not deliver, this did give them their claims, and their holdings were secured in WWII and further legitimized in the current war on terror.
Their Blitzkrieg tactics was so brutal and quick
The purpose of passing the Neutrality Act of 1935 was because once the act was invoked, the US was in a better position to find a diplomatic solution to a conflict.