[From Paul's NY Times page: The marquee for his talk at the Bagdad - Paul , Beer, Oregon - get it?]
Paul's most influential insights came from the idea that there may be increasing returns in trade. When applied to trade this insight helped explain why we see two-way trade in things like cars and was the principle reason he won the Nobel. But this insight quickly spilled over into other areas as well - for example, why is Silicon Valley still the center for high tech industry given that it is perhaps the most expensive place on earth to do business? Paul's answer has a lot to do with heads starts and learning curves: It may be cheaper to move Silicon Valley to Bangalore if you could do it overnight, but you can't - it takes time to build up the knowledge base and skilled work force and while that is happening, Silicon Valley can compete the nascent Bangalore away. This helps explain that while Bangalore has been able to chip away a little bit at Silicon Valley's dominance it hasn't done that much. This story is half trade and half economic geography. Economic geography talks about increasing returns that come from concentration: part of why Silicon Valley is so successful is because of the close connection inventors, entrepreneurs and venture capitalists have by virtue of being neighbors and part is the concentration of skilled workers to populate the firms.
So what does this have to do with Beervana - Portland (and Oregon's) disproportionate number of breweries and beer drinking? Well the same stories about Silicon Valley can be told here: brewing and beer drinking are both learning processes and ones that benefit from concentration. Brewing takes skill and practice and a there are a lot of knowledge spill-overs that comes from brewers talking and sampling each others products. Beer drinkers have to learn about the ingredients, how they taste and develop a palate and taste for the more robustly flavored beers. So the punchline is you tend to have concentration rather than dispersion and that places that get early starts tend to hold onto that advantage - familiar themes from Paul's work.
So really, beer drinkers of Oregon, this Nobel's all about you! Let's toast to that...
By the way, just to complete the circle - Beervana blogger Jeff Alworth left a comment on the same Krugman blog page that includes the picture above.