What can we do about Homeless?

We have homeless persons all over the US and we spend millions to try to build facilities for these people to give them shelter and help them regain control of their lives. What I find interesting is that we close military bases all over the US as well and let the bases just fall apart. Why do we not use these as homeless shelters. These facilities were good enough for our service men that were serving our country, why are they not good enough for our homeless. I would think we could even provide some extra jobs for those on welfare and those homeless to help them get back to living normal lives again.