I think the answer to Marshall's question is that if the Saudis retaliate against Iran, then Iran will retaliate back against Saudi Arabia. Iran is not very far from KSA and it has plenty of hardware that can easily reach across the Persian Gulf to the oil-producing center of the Saudi economy.
If, on the other hand, the U.S. retaliates against Iran for the Saudis, then the Iranian leadership will curse the U.S. and their Saudi stooges, but won't respond militarily against Saudi Arabia because the U.S. will be viewed as the real enemy.
The Saudis have a big shiny military. But they won't use it because they don't want to face the consequences of their actions. So instead they are not publicly pinning the blame for the oil refinery on Tehran, while privately lobbying the U.S. to kill the Persians.
If, on the other hand, the U.S. retaliates against Iran for the Saudis, then the Iranian leadership will curse the U.S. and their Saudi stooges, but won't respond militarily against Saudi Arabia because the U.S. will be viewed as the real enemy.
The Saudis have a big shiny military. But they won't use it because they don't want to face the consequences of their actions. So instead they are not publicly pinning the blame for the oil refinery on Tehran, while privately lobbying the U.S. to kill the Persians.
