can't they just locate servers and bank accounts off shore and use something other than a . com TLD? what could dhs do then?
No is the short answer. Not if you want any legitimacy and longevity. Do you think PayPal founder Elon Musk would be as wealthy as he is or if PayPal would have lasted as long as it has if he'd moved PayPal offshore to avoid US regulation? They (The US government) had Kim DotCom's entire MegaUpload operation terminated... and the guy was living in New Zealand. My point is that you can't work against them (the US or pretty much any Western Government), or at least not for long - and instead you need to work with them (and of course, this costs money and limits your options... E.g. no more cash deposits).
It's a painful and bureaucratic situation, but challenging the status-quo always is.