The United States, built by men and women from diverse cultural backgrounds, is among the most innovative nations in history. Our cultural narrative includes the conception that we’re a “melting pot,” folding different customs into a system of practices that drives our global leadership. Our diversity is the yeasty source of solutions for our many challenges.

However, in the yin and yang of progress, our very success has us cling to outdated ways and refuse admission to new populations. Despite evidence that diversity drives our power, many of us despise Others.

These clannish dynamics are at work in our 2012 election. Political parties and the electorate haven’t been more polarized for 150 years. Party platforms and personal identities are passionately differentiated, and complicated by our ancient fear of the Other.

For millennia, people who were different from us were a threat. Even today we prefer to flock with birds of our own feather—with people who think like us and who make decisions like us—and build literal and metaphorical walls to preserve our communities.

Look at President Barrack Obama. His father was a Kenyan Muslim and his mother a Christian from Kansas. He’s the product of an interracial marriage, born in Hawaii and raised in Indonesia. Many see him as profoundly “Other” and confirming their belief are the presidents engraved on the bills in their wallets.

Even though demonizing Others serves to shut out new ideas—the energy source for innovation and economic growth—we still do it. While the vast majority abhors intolerance and we’ve made its overt expression illegal, the Internet is awash with ugly comments about the President’s Otherness—about his race, birth, parentage, nationality and political legitimacy.

In tolerating such filth, we’ve become our own worst enemy. Confronted with unemployment, debt and war, should we not seek and discuss solutions on which to build, not toxic slurs on which to divide?