If this is OK, what exactly isn’t OK?

The last time that we invited outsiders to participate in a purely American dispute, we were fighting the Civil War and the Confederacy was begging Great Britain to intervene. Now we’re at it again, and it leaves me both flummoxed and deeply worried.

In this case, the outsider is Russia. Confronted by overwhelming, documented evidence that the Trump campaign at least attempted to enlist the Russian government into its cause, defenders of President Trump have an argument that amounts to “so what if they did?”

There are a lot of ways to answer that. The pragmatic response would be to point out that if you take ill-gotten information from Vladimir Putin and use it in your campaign, congratulations: You just became Putin’s pawn. With the push of a send button to his pals at WikiLeaks, he can now destroy you at the moment of his choosing. He knows it and you know it.

Another way is to point out that if this identical scandal were playing out under a Democratic president, with Russian interference not just welcomed, but rewarded and encouraged with Russia-friendly policies, the GOP response would be dramatically different. Fox News would be beside itself, unleashing the furies, and the gears of impeachment would be welloiled and turning. And I just don’t think that under those circumstances, Democrats as a whole would be rushing to defend such behavior or trying to explain that while it looks bad to invite Russia into our political disputes, it’s not illegal or criminal so it must be OK.

I don’t see that happening. But here’s what has me gutsick: Healthy nations don’t do this. Americans don’t do this. We don’t invite outsiders to take part in our fights, to help us battle with fellow Americans. Elections are fought and settled here, right here, within the family. It’s about us, not them. If our internal battles have become so heated that it is now acceptable to call in third parties to help your side win — even third parties that have historically been our nation’s adversaries — then we have lost something important.

That transformation is all the more startling because it comes from a party and president that in every other context claims to be nationalistic.

According to the “America First!” crowd, we need The Wall to preserve the sanctity of our border. We need stringent election laws to ensure that only U.S. citizens vote, to guard against even a tiny possibility that some illegal immigrant somewhere might violate the purity of the ballot box. We also want no restrictions placed on us by international agreements that might impinge on our national sovereignty, while immigration bans and trade barriers are the executive order of the day.

“We want to build with American workers, and with American iron, aluminum and steel....Buy American, and hire American,” as President Trump recently put it. “We have sent a clear message to the world that we will not allow other nations to take advantage of us any longer.”

Yet somehow, when it comes to outsourcing of opposition research to the intelligence agencies of foreign adversaries, it’s stunning to see that obsessive concern for national sovereignty just evaporate. If an immigrant dares to vote illegally, we sentence her to years in prison, but if an entire country picks a side in our election and actively tries to intervene, we’re told it’s no big deal.

If that’s OK, what isn’t OK? What’s left?