How long are we going to sit through this Donald Trump presidential run before we admit what it's doing to the fabric of the country and the fortunes of the GOP? When are we going to stop pretending it's not profoundly destructive to the nation?

The presidential election is still nearly a year away and yet here he is, this bumptious human quote factory, saying or tweeting every outrageous thing he can think of and following it up with something even worse, often within the hour.

Have you read any of the nakedly racist things that Trump has written or said this week? If you did and you let it pass without comment, then the fact is you are tacitly enabling his disastrous candidacy. The joke wore out its welcome weeks ago, and we're in a calamity of another order now.

If you're Latino or African American or Muslim or a refugee then you will already know what it feels like to be targeted by his hateful campaign. Trump clearly doesn't expect your vote, so he is very comfortable trashing your respective communities.

On Sunday on ABC he repeated his horrifying call to keep a database of all Muslims in the United States (that was tried before, you'll recall, on European Jews with historic results).

A day earlier a black activist was roughly punched and kicked on camera by angry voters at his rally in Alabama. The morning after the rally Trump told the hosts of Fox & Friends the black man deserved what he got.

“Maybe he should have been roughed up,” Trump said. “It was disgusting what he was doing. This was a very obnoxious guy, a troublemaker, looking to make trouble.”

How presidential. Protest Trump and he'll support your public assault.

But he was only getting warmed up. On Sunday Trump then tweeted a bogus image about national gun murder statistics. The poster showed the image of a black man with a handgun created by the “Crime Statistics Bureau” in San Francisco.

But Trump's statistics on black-on-white homicides and white-on-white homicides were completely bogus and unsupported by any official sources. They were, in Trump's own parlance, total bulls***. Even the so-called “Crime Statistics Bureau” doesn’t exist.

It turns out that the nakedly racist graphic was apparently the work of a Hitler-adoring neo-Nazi. That means Trump was openly tweeting Nazi propaganda. Does his candidacy still look like a big laugh to you now?

Trump is the Republican frontrunner, the favorite of that party to run for president of the United States. And he's tweeting Nazi propaganda. It won't be long now before the GOP grasp how toxic to their interests his candidacy has become.

Inciting hatred to inspire your base is an age old political ploy. You make the calculation that the people you trash are expendable, and the people that you want to appeal to will love hearing them abused.

This is the Trump model and it appears to be working. Nothing he says, no matter how controversial, has had a negative effect on his poll numbers yet.

After the horrifying Paris attacks the nation needs a commander-in-chief who will call for calm and a measured response to the threat of global terrorism. Instead Trump claimed that thousands of members of the Muslim community in New Jersey took to the streets on the evening of 9/11 to celebrate the Al Qaeda attacks.

“I watched when the World Trade Center came tumbling down. And I watched in Jersey City, New Jersey, where thousands and thousands of people were cheering as that building was coming down," Trump said at the Alabama rally where the black man was attacked.

If I belonged to a community that was daily being abused and libeled by this carnival barker I'm sure I would have raised my voice to protest it too. For his trouble he got punched, thrown and ejected from the building.

No one in New Jersey cheered after the 9/11 attacks. It isn't even an urban myth. It's much more accurate to call it what it is, a bare faced lie.

There are no news reels of this bogus celebration, nor could there ever be. It didn’t happen. But Trump is apparently more interested in playing to his gallery.

The “thousands and thousands” of Americans he threw under the bus won't get an apology.

There is one thing he is doing that is useful, however. Trump is lifting up long forgotten rocks and showing us all the angry racism and xenophobia that still resides under them, and clearly they are as passionate today as when they first burned their crosses.

It's really useful to know that. If only to know what we're up against next November.

How long before we admit what Donald Trump's presidential campaign is doing to the fabric of the country and the fortunes of the GOP?iStock