Understanding Jihad

I can't get a firm grasp on this Jihad thing.  First, there seems to be no restriction on who can call it.  If you are a Muslim, you can call for a Jihad.  Second, there seems to be no way to call off a Jihad.  Only when you have peace, Jihad ends.  Lastly, Jihad seems to be all about striving for peace with allowance for use of force against aggressors as a last resort.  Jihad reminds of how antibodies work except definition of harmful is rather loose.  I suppose if you are living in a sparsely populated harsh environments like Middle Eastern deserts, you need something like Jihad to gang up on anything that threatens their lives.

The strange thing is that, more I read about Jihad, more I am reminded of Bush.  While Saddam and other Muslims are calling for a Jihad, Bush is actually doing Jihad by using force to curb evil.  While he is not a Muslim and it is arguable whether or not there was no other workable alternative, Bush is on a Jihad against Saddam who was threatening peace in the region and at our gas stations.  Since Saddam has been a rather disappointing enemy of war, we'll soon have peace in the region and Bush's Jihad will end.  Jihad is Cool.