I live in the Washington DC area. The general job market is weak to poor. The IT job market is split. The commercial IT market is slow but alive. But if you have a security clearance, then the market is screaming hot, and has been for many years. There is no sign that the market for folks with a clearance (called a "ticket" locally) will ever cool down.
If you read the job postings, the key telling point is that when it says "US citizenship required" its because the position requires a security clearance, which requires US citizenship.
p.s. it is illegal to post a job that discriminates in nearly any other way, but requiring US citizenship is OK if the position requires a security clearance.