Putin's response shows he knows this is a blow to his prestige.
He cared little about the chemical weapons strike. He went into his standard uncertainty response: who knows who really did it? Delay is victory.
He was clearly surprised and furious that it didn't work this time. The noise he is making reflects the fact he was injured by Trump's move. He depends upon the notion that the US is so wrapped up in its anxieties and the niceties of the law that it will never do anything.
Instead of bloviating, Putin should do something to rein in his Syrian poodle. Better yet, remove him. Avoiding WW3 is on him this time.