For me, liberty means having the freedom to do what I want without government interference.
So what has Bush done to protect liberty?
1) Lowered taxes on all tax paying Americans. This gives Americans mroe control over their money.
2) He has pushed for school vouchers so that parents have more freedom of where to send their children to school.
3) He has pushed the most expansive education reform (no child left behind) which requires schools be tested to make sure that they're doing the job they're supposed to do and enable children to go to different schools if their school fails the standards too many times.
4) He has cut down on all kinds of regulations such as various idiotic federal regulations that were creeping into businesses in the 90s such as requiring increasingly small businesses to have their desks and chairs ergonomically correct.
5) His foreign policy has liberated millions of people. Ask a woman in Afghanistan if she has more liberty today than in 2000.
So those are 4 things that I can think of off the top of my head. Feel free to list something a Democrat has done to make us have more liberty recently. Heck, how about naming somethign John Kerry has done in his entire Senate career in the name of freedom.