Should US security contractors operating in overseas war zones be accountable to local governments and local law, or should the firms be accountable under the terms of US law?

US security contractors should be accountable to local governments and local law. The firms are overseas and on other countries' land, so they should obey the laws of the country they are situated in.

I have the opinion that the local and US governments should go hand in hand in such cases. I know that the co-operation between the two can be challenging task but that's the way it should be done.