@BTC Books
The Connect= argument is something I didn't think about.  Anyone who makes it outside the country will be able to quickly propagate their known longer chain within the country - and the problem would be temporarily solved.

But the other answers do confirm my fears that, in one of the places you need bitcoin the most (i.e. in a repressive country) it becomes very dangerous to rely upon bitcoin transactions.  Double spends become real possibilities for someone who can travel or personally access the outside.  As a merchant receiving BTC in this kind of country, I would have very little knowledge and no control over whether my coins might someday just disappear.

So I guess I have to dig deeper into my initial assumptions to know how real this possibility really is.

Is the assumption in the Bitcoin community that governments can't really shut things down effectively enough to cut Bitcoin off (with things like encryption, tor, occasionally walking a USB across the border, etc.)?

It just doesn't sit right with me that there was such intense concern over the (minor and short-lived) fork on Monday.  Especially if governments could effectively force a network fork within their region.  I'm sure many governments couldn't fracture the blockchain without crippling a large part of their own economy at the same time - the internet is just too deeply connected.  But repressive, desperate countries may - and that puts a chink in the "robustness" promise for me.