As I implied above, it's a problem in particular jurisdictions, not necessarily everywhere. China for one is aggressively pro-nuclear. If thorium reactors are everything their advocates think they are, countries that throw too many obstacles in their path will disadvantage their economies.
Aside from that, nuclear reactors don't necessarily have to be gigawatt-size. Even in the U.S., smaller reactors are starting to make some regulatory headway.
But even conventional 1GW reactors don't have to take decades to build. China's first AP-1000s at Sanmen are being finished up this year and next for a construction time of five years.
http://en.wikipedia.org/wiki/Sanmen_Nuclear_Power_Plant
http://www.world-nuclear-news.org/NN-First-Haiyang-AP1000-ta...