[SomeStupidPoint]

But can't they just download the Wikipedia backup, purge the articles they don't like, and redirect the DNS lookup to a local copy?

To the average citizen, it won't look much different than going to actual Wikipedia.

[FreeFull]

This is feasible, assuming the government is willing to pay for the hosting.

[kijin]

As well as forge an SSL certificate for *.wikipedia.org.

Last time I checked, Wikipedia had HSTS enabled. So trying to forge their DNS without also forging their SSL certificate would be equivalent to total censorship for anybody who has previously visited Wikipedia.

[gjjrfcbugxbhf]

Assuming the government in question has access to a root certificate this should be possible.

[sqeaky]

Even presuming it is possible, it still raises the cost of censorship. Simply raising that cost is a good thing.