Doesn't this have case-law re: the DMCA's domain-name seizure process?

The US is perfectly willing to enforce its own rulings on foreign companies operating solely abroad, at the point at which those companies' goods/services enter the US.

So why wouldn't we just assume that every country is going to do the same; and so pre-emptively self-regulate if we want to do business in foreign markets with differing laws?

Canada has every right to say that it will block Google from Canadians accessing it unless/until they censor those pages, not just for Canadians, but for everybody. Given that, and given that Google knows that they could do that, what options are Google left with (assuming they care about remaining available to Canadians)?