[asdfgadsfgasfdg]

It is a similar concept to export of physical goods into a country/trade block. Either comply with the local regulations on quality or your goods will not be allowed.

The US State Department does not really get to have a stated position other than diplomatic.

[Klathmon]

Who will be responsible for the "blocking"?

Will I as a developer or US business owner need to proactively disallow all users from outside the US (since I am not familiar with their laws) to avoid potential legal troubles, or will other countries block my site/service without me needing to do anything?

[tscs37]

It depends on whether or not you are operating under their jurisdiction or not.

If you are, they can drag you to court. End of story.

If you aren't then they will first rely on your cooperation and if that doesn't work, probably issue arrest orders which will make it a bit inconvenient to enter the EU for a while. And they'll probably tell ISPs to block you, yeah.

[gdwatson]

"It is a similar concept to export of physical goods into a country/trade block. Either comply with the local regulations on quality or your goods will not be allowed."

That analogy is what I take issue with. It's clear that Facebook, selling ads to European buyers, is doing business there. But is every random web site with a few European users? Does putting up a web site suddenly mean you're doing business in every country in the world, subject to the jurisdiction of all of them simultaneously?

"The US State Department does not really get to have a stated position other than diplomatic."

Diplomacy is what it does, and its diplomatic position on trade issues is relevant.