In a fight between a polar bear and a lion, the polar bear would win

Polar bear is bigger. The lion couldn't survive the cold. In the African savanna the polar bear would lose. However, both are dying as we are destroying their habitat.

You'll have to bear with me here...
But..

You won't ever win with lion.

sure you can, in fact most lions win, truthiness is a rare and fragile commodity easily defeated. what else could be meant by "he was lionized"?

But I think Colbert has shown he would side with the Polar Bear since he doesn't want to have to go back to the cold.

Forest ranger's opinion: A polar bear is the largest land carnivore on earth. Some polar bears can easily weigh more than twice as much as a male lion. No contest. Polar bear would dominate. They can weigh more than twice the weight of a lion and have huge paws and deadly jaws.

Polar bears stand around 5.3 feet at shoulders. Lions fight with help of their powerful forequarters and the bear's forequaters being more strong it will easily overpower the lion.

Although it is a heavy creature the polar bear is still astonishingly agile.
So in the end no big cat stand a chance against this great bear in a one on one fight. If lion is ''king of savanna'' and tiger ''king of forest'' then polar bear is ''king of arctic." Bear wins 8/10 times.

Most predators avoid getting into unneeded fights with others predators as even the winning side can end up starving to death if they suffer some wounds that interfere with future hunting.

Polar bear ripped apart the lion but in doing so have one back leg ripped open slowing him down so he can not pursue his normal prey animals.

Pack predators such as lions might survive thank to his pack mates but the bear would not.