Nasa scientists believe they have found proof of present life on Mars and are currently getting their work peer reviewed for publication in Nature.
http://www.space.com/scienceastronomy/mars_life_050216.html
This would be a provide a big boost to the President's desire to send manned missions to Mars.
Yes, I do believe that manned missions to Mars are an excellent use of our taxdollars, as the technology we could gain from the mission (set aside possible research) would greatly offset the cost. Plus, I envision a corporate sponsored "reality" mission that would follow the astronauts on their journey on tv, which would help offset the costs.