Convention season is upon us.

Hordes of salespeople will gather this week in Denver and beginning Labor Day in St. Paul, intent on pushing their products to the their cohorts and to the American people at large.

But they won’t be selling goods or services, not in the conventional sense.

No, these salespeople want us to buy their ideas.

Today, Democrats convene in Denver. Nominee Barack Obama, running mate Joe Biden and a seemingly endless cast of other speakers will attempt to rally the troops and convince those Americans watching that the Democ...