Syria chemical weapons facility raid, for which the US President gave ample warning, was designed to trigger Syria anti-missile defense to see what they've got and gauge the Russian input.
Except they'd already done that a year ago with the attack on Shayrat airbase. But you are correct that there was certainly another motive, since if the Syrians were making or storing chemical weapons, a high energy attack is very likely to release any agents stored there. From which I conclude that the targets were more likely comms or intelligence facilities.
Biting the hand that feeds IT
