Exactly. Does not matter what country you live in. If you happen to live in a country with no extradition treaty, you will never be able to enter the U.S. again without being arrested and it's highly likely you will be arrested in most countries you step into.

The days of hiding in the Caymans or in Switzerland are over.

That isn't necessarily true. It isn't uncommon for stocks to exist that are traded on local exchanges that equal a set number of shares on a foreign exchanges. They vary by market, but they are called ADRs in the US. It is doubtful that any of these exist for a stock like Twitter, but it would be an easy way to benefit from American stocks without having an American brokerage account.