This is not your ADHD, this is some sort of antisocial behaviour, maybe driven on by one or more (maybe undiagnosed) personality disorders.
I'd recommend at least getting checked by a professional in the field (psychiatrist perhaps, depending on your country) so you can find out what is driving this behaviour, and then you can make a decision on whether you want to address it or not. Knowledge is power and knowing more about yourself is helpful, regardless whether you decide to address it or not.
Why anyone would voluntarily choose to go to the USA these days is beyond me!