My experience with the Chinese Great Firewall over the last year-plus has been weirdly variable. Sometimes I can get to almost any site I'm interested in, even without using a proxy server or VPN. Sometimes a large number are blocked. With a proxy server, of course, almost anything works.

For the last few days I've been in circumstances where I can't use my normal proxy server. And here's what I find:
- Wikipedia -- all entries blocked
- Blogspot -- all blogs hosted there blocked
- Blogger -- ditto
- My pre-existing personal site, on WordPress (jamesfallows.com) -- blocked, so I can't put any posts or updates there

Yet BBC.co.uk -- often impossible to reach from within the Great Firewall, today is wide open without problems. And so is the very-frequently-blocked Technorati.

My intuition is that the offs and ons of the Firewall have as much to do with inadvertence and happenstance as with some coordinated master plan. But this is tighter control, or at least more broadly obstructive control, than I've noticed in a while.

Is it due to the Burma upheavals, to diminish awkward discussion of China's role? I don't really think so, because Burma-related sites not on Blogger or Blogspot come through - plus lots of news on the BBC (which forthrightly calls the country "Burma.") Run-up to the 17th Party Congress, which begins in about three weeks, and before which there's been a general attempt to damp down controversy of any kind? For now I don't know the cause, only the effect.

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