LOL. Assad supposedly kills a handful of people with illegal weapons because he has everything to lose by doing so and nothing to gain? I guess some posters on here haven't been following middle east events over the last few years. As pointed out by numerous posters the USA is the aggressor, both directly and indirectly, and has the blood of hundreds of thousands on it's hands.
It's more likely that a rebel held weapons cache, which included chemical weapons (!), blew up and released the gas. We don't know what caused the initial explosion, although it could have been a bomb or missile from the Assad forces trying to destroy the cache.
As for Trump, what was he supposed to say? A handful of civilians died but it's nothing compared with the hundreds of thousands already dead, so relax, you'll get over it soon enough? No, he had to make all the right noises as all politicians do.
My guess is that Trump will be fed the real facts soon enough, either from within the administration of from numerous alternative media reports, and he will back off causing any hostilities with Russia.