That's woefully poor analysis. Thailand did not fight wars from the 50's to the near 80's. That's a bit like asking the former Yugo states why their economy looks nothing like Turkey's.
It's hardly surprising that the communist government went crazy-anti-capitalism after having half the country turned to mush by the Americans, but things are getting better. After the war, the communists didn't even allow privately-owned shops, and the economy was awful. They started reversing that and the economy started recovering.
But just because somewhere else is doing better doesn't mean that a place hasn't improved significantly in recent years. That's a boom.