I'll call your attention to "Should the US formally declare war on ISIS?"
There are no "boots on the ground" in Syria as per policy, but there are American soldiers wearing boots engaging in combat activity in war zones in Syria on the ground. Except as they're not officially "boots on the ground" everybody likes to pretend the US isn't actually involved in Syria yet.
And when it comes to the decision whether to actually send humans who risk their lives and will be held accountable if they screw up, or to just continue drone strikes or bombing raids with no public accountability unless a military plane is downed -- I will prefer boots on the ground any day. War is hell. Drone war just allows one party to distance itself from the hell it is engaging in.
Again: we know Clinton's stance on war and the Middle East, Russia and China. Clinton already holds a lot of political power in the US (just look at her campaign's biggest sponsors and the Clinton Foundation -- plus the entire thing with her having been the de facto blessed Democrat candidate since before the primaries even started). Trump is an outsider who has the majority of the country against him (the GOP is still reluctant to present him as "their" candidate).
Hyperbole aside, the POTUS is not actually an autocrat. There is still a large body of bureaucracy and checks and balances preventing the POTUS from doing as (s)he pleases. Clinton would only have to worry about the Republicans, Trump would likely have everyone against him at some level.
He's not innocent, but he's significantly less dangerous. He's controllable (recently he went so far as to suggest that he would cede most of his duties to his VP -- effectively just leaving the prestige and title). Clinton is not (she already has an actual agenda and is far more nuanced when it comes to manipulating people in her favour).
Don't get me wrong: I don't want to see either of them become president. I would have loved to see Sanders win the primaries (simply because to me as a European he felt like a healthy counterbalance to the usual American politics) even though I was certain one of the other Republicans would have eventually won the election. But at this point you're basically forced to choose between Chaotic Evil with no political support (i.e. built-in limitations to the damage he can do) and Lawful Evil with an entire body of politics behind her (i.e. a lot of paved roads).