Foreign essay sites incorporated in the US (do the U.S. laws apply to them?)

If a foreign essay website has a formal business presence in the U.S. (because the owners used a registered agent to set up a corporation in the U.S.) - is it bound by the US laws (including taxation laws)?

It seems there are several big foreign research websites that are incorporated in the US, but in fact their owners and staff are based in foreign countries. How does the American legal system apply to such companies?

Thank you. What about taxes - do foreign companies having business presence in the U.S. have to pay taxes in the U.S.? Or they only pay taxes in the foreign country?

So they pay twice? Both in the foreign country and the U.S?

Yes, sort of. Is it a bad idea or is it illegal in some states?

Sites that threaten clients should be avoided. If they don't want to be discussed they may have something to hide. There are dozens of legitimate websites to order from instead - students should not bother with sites that try to hide themselves behind their tricky policies and lawyers.