Thomas Jefferson was homeless for 12 years on the streets of Philadelphia after returning as a combat veteran from the battlefields of Iraq. "When I came home, I was messed up," he said. Mr. Jefferson struggled with substance abuse and had a stroke, ending up in a wheelchair. Now 45, he lives less than a mile from where the man who became the third president drafted the Declaration of Independence. He is pictured in the Assembly Room of Independence Hall, where the document was adopted on July 4, 1776.