Career consultant Derrick Dortch has reassuring words for security clearance applicants who are worried about being approved: “No one is perfect,” he said in a recent interview. “All of us have made mistakes and have blemishes in our backgrounds. So don’t assume that any mistakes you may have made in the past would necessarily doom your application for a security clearance.” A variety of factors, including the particular clearance policies of your target agency, would likely influence the importance of your mistakes or liabilities, said Dortch, who is president of the Diversa Group, a career consulting firm focused on federal…