Yeah. For all of Boston's history it's simply not that important a target in terms of global thermonuclear war. It doesn't have the political stature of DC or the financial stature of New York. And it's actually pretty small; it's the 24th largest city in the US by population and the Greater Boston area is the 10th largest metropolitan area in the country. We're way smaller and way less tasty a target than NY, DC, LA and Chicago.
As for Las Vegas, well, that's simple: it's the poster child for Western decadence. Of course the commies nuked it.
-- Rat That and five bucks will get you a small coffee at Starbucks