Difference between Muster Up and Unpower

MUSTER UP vs UNPOWER: NOUN

Sinewless, Good part, Unstrength, Strengthful, Fortitude, Revigorate, Strength, Innerve, Sthenic, Sthenia, Courage, Come up, Rally, Summon, Muster

Pluck up, Sinewless, Good part, Unstrength, Strengthful, Fortitude, Revigorate, Strength, Innerve, Sthenic, Sthenia, Courage, Come up, Rally, Summon

How do we muster up the courage to turn down new invitations while still keeping friends close?
Congressmen can muster up against the war in Iraq is tosay let Congress vote on it.
But can they muster up some points on offense against the very stingy Steeler defense?.
Maybe he could even muster up the courage to explain his feelings by then.
Tom Hanks was able to muster up a handful of anecdotes for print.
But TODAY all Old John could muster up was attacks on Obama.
He used pathos to muster up superior performances from ordinary citizen soldiers.
Bill right and muster up strength for him.
You better muster up some will to fight.
Can we pull ourselves together, muster up our civic pride, collective chins up, and move forward?.