06 Liberty won't start. If it's not the battery, starter, or ignition actuator then what can the problem be?

The obvious problems seemed to be bad
battery, bad starter, or broken ignition
actuator. I thought I'd try the actuator first.
Got it all apart from the steering column, but
was having difficulty separating the
actuator from the switch. On a whim, I stuck
the lock cylinder into the actuator in my
hand and gave it a turn. The engine started
right up, but when I put it all back together
on the column it won't crank.