Mocking the weak is not a desirable trait in someone seeking the most powerful office in the world.
Donald Trump would be in hot water if he were any other candidate but he’s apparently immune to such things mainly because so many love the way he confronts the media. His candidacy, while built on his immigration stance, has persevered because many refuse to let the media take him down. It’s not just appreciation for Trump, it’s anger at the media.
But Trump’s latest is, I think, revealing of his character. And it’s not pretty. He apparently did not just mock someone with a disability but he may very well have mocked him specifically for his disability.