The US can enforce it laws on anybody it can get its hands on. For example Joaquin Guzman, the drug kingpin recently captured in Mexico faces charges in a variety of US states, even if he never set foot there. [1]
Mexico has to agree to hand him over, but once the US has him, they can happily convict him of crimes committed while he wasn't physically present in the US.
Mexico has to agree to hand him over, but once the US has him, they can happily convict him of crimes committed while he wasn't physically present in the US.
[1] http://www.npr.org/2014/02/25/282359473/arrest-of-el-chapo-n...