Washington — As Mueller time approaches, it is likely that President Trump’s defense will consist of two phrases: “But that is not illegal” and “But that is not impeachable.”

It is a strategy that prevails by the lowering of standards. Because Trump did not plot election fraud directly with Russian President Vladimir Putin by Skype, and because Trump’s various crimes and misdemeanors do not constitute high crimes and misdemeanors, we should consider the president vindicated. Unable to make the case for his own virtues, Trump must aver that his vices are commonplace and inconsequential.

Will this work? If the only standard of success is keeping enough Republican votes in the Senate to avoid Trump’s removal from office, it may.

It is now fully demonstrated that the Russian attack on the 2016 election was broad, ambitious and designed to give Trump practical aid. Russian intelligence fed ideological and racial tensions in a sophisticated attempt to arouse enthusiasm in Trump’s base and dampen enthusiasm for Hillary Clinton among minority voters. Did this tilt the election toward Trump? Given that Trump prevailed by 107,000 votes in three states — out of 120 million cast — I think it is both likely and unprovable.

Consider this outcome from two other perspectives. If you were the head of Russian intelligence, I suspect you would currently have a chest full of medals. And if the political circumstances were reversed — if Clinton had received Russian help to become president — every elected Republican would diagnose a conspiracy that undermined her legitimacy. Every. Single. One.

But the Russians did not succeed by hacking voting machines in the upper Midwest. They saw an opportunity in the rise of social media and the strength of nativism and racism on the American right. They seem to have exploited a national weakness without invalidating the election itself. The Russians really didn’t need to go very far to find a template. In inciting racial and ethnic tensions through obvious propaganda for the benefit of Trump, Russian intelligence was simply following the Fox News business model.

Does it make a difference if special counsel Robert Mueller describes extensive contacts between Russian officials and the Trump campaign? Or that senior campaign officials systematically lied about those contacts? We have known of such cooperation and such lying for years. Campaign officials such as Donald Trump Jr. were eager for collusion with shady Russians. Trump publicly invited Russian hacking of Clinton’s emails. Trump’s lawyers will continue to argue that, however unseemly these things may be, they are not illegal.

Will it make a difference if Mueller reveals corrupt business dealings between Trump-owned companies and Russian oligarchs? It certainly helps explain why Trump was an obvious politician to favor. He holds the oligarch’s view of business integrity. He supports the oligarch’s view of economics, in which outcomes are determined by family-run cartels that have taken over the levers of government. But unless Russian intelligence is actually blackmailing Trump, I’m not sure that suspicious, or even corrupt, dealings with the oligarchs is unexpected. Trump has bragged about buying American politicians. He has bragged about using bankruptcy laws to exploit his investors. He has often argued: I played by the rules as I found them. Elected Republicans may place money laundering through real estate in the same category.

There is the problem for Trump. When all this evidence is stitched together in a narrative — as Mueller’s report will certainly do — the sum is greater than the sleaze of its parts. Russian intelligence officials invested in an innovative strategy to support the election of a corrupt U.S. businessman with suspicious ties to Russian oligarchs. The candidate and his campaign welcomed that intervention in public and private. And the whole scheme seems to have paid off for both sides.

For the rest of us, the deal hasn’t worked out so well. A deeply compromised American administration has been unable to effectively counter a direct attack on our democratic institutions by a hostile foreign government — responding to a digital Pearl Harbor with a wink and a nod. “This is an existential constitutional crisis,” says historian Jon Meacham, “because it’s quite possible that the president of the United States right now is a witting or at least partially witting agent of a foreign power.”

Some of us are still too shocked to process this. America seems to have gone from zero to banana republic in no seconds flat. But whether or not this transformation has been illegal, it must be impeachable — or else impeachment has no meaning.

— Michael Gerson is a columnist for Washington Post Writers Group.