Well it's not all bullshit, morality is part of the decision making, but national security interests probably weigh in far more heavily. The use of chemical weapons is very serious. Whoever thinks the allies would stand by and wait to see what happens is naive. Is attacking Syria the right thing to do? Who knows, history will tell soon enough.
But having someone use chemical weapons anywhere in the world in the 21st century is not compatible with NATOs security standards. The assumption was that Assad had his stuff under lock and keep, that it was off limits. Now it turns out it's not. Either he's not fully in charge of his military or he himself allowed it. Either scenario is a massive threat that has to be dealt with. What if these munitions make it out of Syria. It's not in anyone's interest that this happened.
But having someone use chemical weapons anywhere in the world in the 21st century is not compatible with NATOs security standards. The assumption was that Assad had his stuff under lock and keep, that it was off limits. Now it turns out it's not. Either he's not fully in charge of his military or he himself allowed it. Either scenario is a massive threat that has to be dealt with. What if these munitions make it out of Syria. It's not in anyone's interest that this happened.