The Saudis won’t do anything to Iran. They are too fat, too soft, and too corrupt. Any war of extended length will wind up instead toppling their top-heavy regime. The Saudis defense policy until now has been to instill fear in oil markets and let the blue-eyed infidels fight their wars for them
Bingo! The Saudis may huff and puff but they'll never actually do it themselves. The Israelis would be fools to trust the Saudis - and they're definitely not fools.
There are the ultra-rich Saudi's (House of Saud) and a whole bunch of "not rich" Saudi's. The rich want to stay that way, and Iran is a threat. The U.S. has provided them with good equipment and bases for years. It's about time they used them to protect themselves. Huge added bonus is using the "enemy of my enemy", Israel.
The Saudis are probably training thousands of suicide bombers with Davy Crocketts.