In the end the Democrats and the Republicans need each other. Especially BECAUSE their opinions are different and NOT IN SPITE OF THEM.
The power of democracy prevents people from pushing their ideals too far, and anyone in charge would when there is no kind of opposition at all. In fact the opposition is tasked to criticize the people in charge, and these critics keep one sharp. And idea should not be deemed bad merely because it came from the Democrats or the Republicans... An idea should be deemed bad when it contains things that could be potentially harmful when not thought through. Errare humanum est. Democrats and Republicans are humans. We need other humans to correct us.
I must respect McCain for stating that he didn't like the leftists, but still acknowledged that he needed the leftists to remain sharp, and that sometimes a leftist idea can, no matter how much he disliked it, still be the better option to deal with certain situations.
Dividing won't help. Unless you wish to destroy a nation. If that nation is the U.S. or Canada or Germany, the UK, Mexico, or whatever nation you can think of doesn't matter. A nation is only as stable as much as people are willing to stand together even if they don't agree. In the end a decision must be made, and decisions that make 100% of the population happy don't exist.
Hopefully Trump's administration was a wake-up call. Whoever succeeds Trump whether that be Biden now, or somebody else in case Trump gets a second term (still possible you know), will have the hard task to unite people again even with the differences they have... I wouldn't wanna be president under those circumstances to be honest.