If the top hose is cool and the bottom hose is hot you've already found the problem.
It's not moving water.
Take the top hose off the radiator and turn on the pump. Does water come out?
If not, pull the thermostat and see if the pump pushes water out the top of the pump.

The only other culprit would be the bottom hose sucking shut but if the bottom of the radiator is hot water is moving through it.

We are brothers and sisters doing time on the planet for better or worse. I'll take the better, if you don't mind.
- Stu Harmon