The US bankrolls and support military regimes which are no less brutal, aside from the actual slaughter it carries out by drones and airstrikes, which is considerable.
There is a reason why many people in Iraq joined ISIS. Their government was executing, torturing and raping Sunni muslims-the one the US installed. They turned to the only force believed could protect them and made a deal with the devil. They were wrong to do so but it is easy to pontificate when it isn't your family that has been murdered.
There is a reason why the people join the Taleban. The primary reason was that the Taleban wiped out paedophilia: a practice the US-backed government current Afghan government legalized.
These are two examples in a very long history of bankrolling and supporting morally bankrupt regimes. This is generally how the US operates: it doesn't get its hands dirty. It doesn't do that much itself other than drop bombs on people wishing away any civillian casualties on "collateral damage" (an excuse flatly contradicted by human rights organizations). It just franchises out terror and tyranny to local proxies and turns a blind eye to whatever they do. however repugnant.
This incidentally is why the US is very unpopular abroad. It is actually the precise opposite of Bush's famous "they hate us for their freedom"-they actually hate you because you replaced popular leaders with dictators who were happy for US corporations to operate.
Some sources:
https://en.wikipedia.org/wiki/List_o..._United_States Authoritarian regimes sponsored by the US.
http://www.independent.co.uk/voices/...s-8911529.html Paedophilia in Afghanistan.