10-year Treasury yield just hit levels we haven't seen since 2007.

Last time rates were here, we were months away from the financial crisis. Different setup today — stronger banks, tighter lending standards, no subprime contagion — but the comparison matters.

Higher rates eventually break something. They always do. The question isn't if, it's what and when.

Watch credit spreads, watch housing, watch anything levered. History doesn't repeat but it sure rhymes.