Jeep liberty wont start

make sure the batt. terminals are clean and tight and try a jump start

As beatupchevy said, check the battery terminals. If they are in good condition, I would check the condition of the contacts on the starter. If the battery is in good condition but the starter is acting like the battery is dead, I would say there's definitely a problem on a contact somewhere or fouled insulation that is causing voltage/amperage issues to the starter.