Well, because while that's a popular theme in United States history, it's not relevant here. The websites in other countries would not be literally sued into oblivion if their servers aren't in U.S. territory - they'd be blocked via DNS intervention.
So, really, the United States wouldn't be extending its law to apply anywhere else but the United States. It would be blocking what content is viewable within the borders. But this isn't even the real issue - because you can still bypass this using the IP address directly instead of the domain name. The real issue is the corporate abuses which could be allowed to take place within our borders if websites aren't deemed to be doing enough. It could make the internet environment tyrannical in content control for fear of websites being shut down.
So, really, the United States wouldn't be extending its law to apply anywhere else but the United States. It would be blocking what content is viewable within the borders. But this isn't even the real issue - because you can still bypass this using the IP address directly instead of the domain name. The real issue is the corporate abuses which could be allowed to take place within our borders if websites aren't deemed to be doing enough. It could make the internet environment tyrannical in content control for fear of websites being shut down.