Nuclear fusion engines to propel humans to Mars

Using energy released from a fusion reaction to power a space-vehicle has been talked about for a long time. Now it appears that scientists are closing in on something efficient and doable. The efficiency is noteworthy because the problem in previous fusion experiments has been that the energy required to start the process has been greater than the energy produced, which is obviously not ideal. The newest technology encases plasma in a magnetic field which is then compressed using lithium rings to a point where fusion is initiated - say the fusion of two hydrogen atoms to create a helium atom. The energy released is funneled out through the back of the spaceship to create thrust.

Driving an engine in this way could apparently get a spacecraft to Mars in 30 days, as opposed to the current 250 days when traveling at speeds of up to 5,000 meters per second. If it takes that long traveling at those speeds, I am amazed to think of the speeds necessary to get you there in 30 days. I'm seeing ridiculous numbers like 343 km/s and even 700 km/s!

For your perusal:

http://scienceblogs.com/startswithabang/2013/04/17/missions-to-mars-and-nuclear-fusion/
http://www.washington.edu/news/2013/04/04/rocket-powered-by-nuclear-fusion-could-send-humans-to-mars/
http://en.wikipedia.org/wiki/Fusion_rocket