There have been presidential candidates who avoid speaking to certain media outlets before, but this is the first time a candidate has completely revoked media credetials for a major well-respected newspaper. Even President Nixon, who was driven from office by the Washington Post, wouldn't have dreamed of doing something like this.
Donald Trump is a new kind of politician. He did it because he said the Washington Post was dishonest in reporting his completely crazy insuations yesterday, when he implied that President Obama had some sort of "other" reason for not saying the words "Radical Islamic Terrorism". It was a clear insuation that Obama must be Muslim, and/or somehow sympathetic to the terrorist cause, which of course, is completely outrageous, ignorant, and moronic. That's what the Washington Post was pointing out. If that's not exactly what he meant, perhaps he should explain it, rather than banning an entire newspaper (one of the three or four finest papers in the country) from attending his events.
You can't just say crap like that anymore, Mr. Trump. That's why we have a free press in this country. To hold our politicians accountable. If someone said that about you, you'd be in court right now.
This a great Washington Post article about the way Trump spreads inuendo. It's called "A lot of people are saying".
Here's another piece by Post columnist Dana Milbank. He has even more examples.