It would have been easy to scoff at the fact that the president of the United States sat down last week to field questions delivered via a social network that limits all messages to 140 characters or less. But the “Twitter town hall” was much more substantive than you might have expected. The questions President Barack Obama answered (which were selected by Twitter executives from the thousands that came in) mostly concerned the economy, but also covered such topics as energy, education, taxes, and our various wars. In other words, it turned out largely as Obama intended, and no one should have been surprised.It might seem counter-intuitive, given how little Americans (on average) know about politics, and how many of us believe ridiculous things - that aliens are abducting people, or that whether you’ll meet an old friend today is determined by the position of the zodiac. But town halls have been with us since before we were an independent nation. That, of course, is part of the appeal: by conducting something like the Twitter town hall, we are updating a hallowed tradition of American democracy to the electronic age.