Quote Originally Posted by drone View Post
Which they already have done. Twitter will be affected, advertisers lose the market, and advertisers with a presence in Turkey might face sanctions if they continue, but Twitter and it's employees should be fine (as long as they don't decide to visit).
Prety much, yeah.

And the legal phrase for retroactive laws is ex post facto. According to wiki, ex post facto punishment is prohibited by Article 38 of the Constitution.
There is more than one constitution in the world and constitutions can change. There have been examples of laws applies retroactively in modern history, but, as I've said, it's rare and unusual.