Douchebags are typically smug, and exude self-confidence. However, rarely are they actually self-confident, but are usually more likely lacking self-confidence. There are the rare breeds that are so deluded that they believe they are cool, when no one else thinks so. In this case, they are not lacking self-confidence, but are just deluded.
From popular culture:
John Denver (as seen on Southpark)
John Denver is the biggest douchebag in the universe.
John Denver (as seen on Southpark)
John Denver is the biggest douchebag in the universe.
by Heidi Wicks November 28, 2007