If that were enough, I think we'd have a lot more nuclear plants in construction.

The problem with this theory is it takes too long between the step where the boosters sell the town with job creation and when the plant can't be cancelled. If you get a city on board today, chances are you won't have a permit in 10 years, and you need to keep them on board the whole time until the permit is issued or they'll derail the permit. It's better to keep them on board at least until the reactor is fueled... but once it's fueled, the jobs engine will probably sustain itself.