Justness in Syria

The Syrian war seems like something the US probably shouldn't have gotten involved in. I think the US in general, or at least the leaders of the country, believe that the US should act like a form of global police.  Over the last decade(s), the US has had its hand in the cookie jar of many other countries.  I'd say the biggest reason we feel we have to be involved as a country is because of the possible threat on our way of life. I don't think it's unclear that most countries on the other side of the world (Syria/Iraq/Afghanistan) aren't the fondest of the US, so they could be a problem (whether it's the actual govt or being a main hub of terrorist activity, who knows).  I believe that as long as our actions in the country aren't shady (covert assassinations, rogue bombings, etc)  that what the US does regarding Syria is (relatively) justified as long as they are in the best interest for our country/not going to start a WWIII.