How do you know you don't like hemlock???

I've been on the road for what feels like forever, which helps explain my paucity of posts. Glad to see that Donpedro has kept the fire burning hear at E4O.

This one isn't about economics per se, but instead about common sense.*

John McCain has been telling anyone who'll quote him that it's a colossal sin that Barack Obama formulated his Iraq policy before he even went to Iraq! I'd thought that this criticism was so self-evidently ridiculous that McCain would be made fun of and then stop making it. But it seems I was wrong. Since McCain's criticism has been reported widely and mocked little (if at all), perhaps its silliness bears some explaining. But first, let's consider some analogical examples:

• I have always wished to own a Ferrari. I like flashy high-performance cars, and everyone knows that Ferraris are among the best. But few people, including I, have ever actually driven a Ferrari. Apparently, everyone would be roundly rebuked by John McCain for formulating a Ferrari-liking policy before ever driving one!

• I live in the Sonoran desert of Arizona, where Black Widows and the Arizona Brown spider are relatively common. Since moving to Arizona, I have tried hard to avoid being bitten by one of these spiders, since their bites are known to be painful and potentially disfiguring or fatal. But since few people have ever been bitten by these species of spider, John McCain would mock me for wanting to avoid Black Widow/Arizona Brown bites before even being bitten!

• I believe that John McCain's gas-tax holiday proposal is really silly, because I believe that it would make very little difference to the gas prices consumers pay while also depleting the Federal Highway Trust Fund. But now I realize that John McCain would mock me for thinking this before I've ever visited the Federal Highway Trust Fund!

• I'm not a supporter of ethanol subsidies, a policy that Barack Obama has supported. But come to think of it, John McCain would mock me for opposing Barack Obama's position before I've ever visited an ethanol refinery!
  

Ok, enough with the examples. Hopefully by now the silliness of McCain's criticism is clear. All of these examples involve cases in which reasonable people can come to beliefs about the world in ways other than direct observation: I've seen Ferraris drive by and have read about their high performance; I've seen pictures of poisonous spider bites; I'm an economist and understand how markets work and so know what the effects of the gas-tax holiday would be; I'm an economist who reads newspapers and thus understand that ethanol subsidies both are likely to and appear to have had some bad effects. In these examples, personal observation or experience is either unnecessary, undesirable, or beside the point.

In some cases, personal observation or experience can be very helpful to formulating a position (turns out I really like the arugula in Italy -- hard to know this without trying it). In others it is beside the point.

Iraq/Afghanistan policy is much closer to the latter case than the former. One can learn lots of information by reading the news, reading blogs, and even by using, say, the laws of reason. No doubt, as a sitting U.S. Senator and presumptive major-party presidential nominee, Barack Obama has access to even better sources of information that these! Can any reasonable person seriously believe that a scripted, days-long trip to the region is more important than his using those sources effectively over an extended period of time?

I do not mean to suggest that Obama's trip to Afghanistan and Iraq (as well as other countries) is or necessarily has to be useless. Indeed, there is much to recommend such a trip. However, a day -- or even a few days -- doing canned visits to and meetings with foreign politicians, American troops and (say, in McCain's case) dangerous open-air markets with a regiment of U.S. Marines and air support strikes me as a particularly unreasonable sole basis for policymaking.

If you think I am wrong, then please tell me:

• Do you have views about appropriate policies for Iraq/Afghanistan? Have you failed to visit Iraq/Afghanistan? If you answered "yes" to each question and think McCain has a point, then please deride the person in the mirror when you brush your teeth tonight.
  

• Will pro-long-term-American-presence pundits who have never been to Iraq withdraw their stated positions and declare their own incompetence to prognosticate?

• How frequently must politicians attend Iraq visits to be qualified to propose and make policy, i.e., what is the half-life on such visits? Where can I find out who qualifies so that I can ignore the others?
  

*Ok, it is true that I think economics is largely about common sense. Or, at least, that's what my forthcoming co-authored textbook will claim.