Most Americans dont care either way until they see visible consequences of actions taken.
Both.
If Americans kept out of everyone else business, there wouldn't be any "Syrian civil war".
Taxpayer money pays the combatants and supplies the munitions. Meanwhile, school kids leave their house hungry in the morning and non insured health care suffers.
Mexican Drug War is a joke. The customers are the American junkies. The nice people with the Alcohol, Tobacco and Firearms do there darnedest to stop the mules, subs and aircraft coming into country, but other US agency operatives and judiciaries receive slush money on the backside.
Good gig if you can do it.
The Mexican Drug War has more immediate effects on the US obviously.
However the Syrian civil war is important because reducing the number of countries ruled by totalitarian dictators is a good thing for long term stability, peace and prosperity.
The price of bananas.
I dont think theirs nothin moar important in the whole world then farts!
The Syrian Civil War or the Mexican Drug War.