WHY is it unsettling to see Republicans and Democrats squabbling, afresh, about Russian meddling in last month’s presidential election? After all, the basic allegation being debated has been out there for months: namely, that in 2015 and again in 2016 at least two groups of hackers with known links to Russian intelligence broke into the computer systems of the Democratic National Committee, as that party’s national headquarters is known, and into the private e-mail system of such figures as John Podesta, the chairman of Hillary Clinton’s presidential campaign, then released a slew of embarrassing e-mails to Wikileaks. Before the election a joint public statement by the director of national intelligence and secretary of homeland security said that intelligence agencies are “confident” that the Russian government directed the hacking. That statement did little to sway supporters of Donald Trump, who heard their candidate cast doubt on that intelligence finding, and instead revel in the contents of the stolen e-mails as they hit the press. This, Mr Trump, suggested, was just more evidence that his opponent deserved the soubriquet “Crooked Hillary”.

All that has changed materially in recent days is that—thanks to reporting by the Washington Post and New York Times—we now know that the CIA briefed senior members of Congress before and after the election that, in the consensus view of intelligence analysts, the Russians’ motive was not just to undermine confidence in American democracy generally, but actively to seek Mrs Clinton’s defeat. These latest revelations have probably not changed any minds at all. Republicans who hate Mrs Clinton are still delighted that she was defeated. Democrats who loathe and fear Mr Trump have one more reason to dislike him. Outside Washington, red-blooded Americans who mostly rather dislike President Vladimir Putin (pictured), according to polls, seem to be shrugging off the latest allegations: President-elect Trump was loudly cheered by spectators when he turned up in Baltimore on December 10th to watch the Army-Navy football game, an annual pageant of patriotism.

And that is what is, or should be, so unsettling. Russian interference in elections across the Western world is like a nasty virus, attacking the body politic. Normally, America is protected by powerful, bipartisan immune responses against such a menace. It also boasts some of the world’s most sophisticated intelligence and cyber-defences, and when spooks tell the Republicans and Democrats who lead Congress and sit on the House and Senate intelligence committees of hostile acts by a foreign power, love of country generates a unified response. That immune response is not kicking in this time.

The problem is not that all Republicans in Congress dismiss the claim that Russia tried to meddle in the election. Committee chairmen have promised urgent hearings. “We cannot allow foreign governments to interfere in our democracy,” said Representative Michael McCaul, a Texas Republican and chairman of the Homeland Security Committee. Senator John McCain of Arizona, chairman of the Senate Armed Services Committee and no friend of Russia, told reporters: “Everybody that I know, unclassified, has said that the Russians interfered in this election. They hacked into my campaign in 2008; is it a surprise to anyone?” The chairman of the House Intelligence Committee, Representative Devin Nunes of California, has said that he believes Russia is guilty, but then turned his fire on the Obama administration, saying that President Barack Obama’s desire for a “reset” of relations with Moscow had led him and his spy chiefs to fail “to anticipate Putin’s hostile actions.” He grumbled that Team Obama had “ignored pleas by numerous Intelligence Committee members to take more forceful action against the Kremlin’s aggression.”

Yet Republicans are not conceding a more incendiary idea: that the authoritarian, anti-American government of Russia wanted Mr Trump to win. Mr Nunes, a prominent Trump supporter during the election, calls that “innuendo” based on “lots of circumstantial evidence, that’s it.” Other Republicans are taking the view that it is all very complicated and murky. “All this ‘news’ of Russian hacking: it has been going on for years,” Senator John Cornyn of Texas, a member of Republican leadership, tweeted: “Serious, but hardly news.”

A startling report in the Washington Post described Republican and Democratic members of the House of Representatives being briefed in a secure room at the Capitol last week and remarking, out loud, that they appeared not to agree even on basic facts, let alone their interpretation. According to unnamed officials quoted in the Post, some Republican members agreed that Russia was a hostile actor, but then argued that logically that meant the government in Moscow would be more likely to want Mr Trump defeated, because he has promised to build up the American armed forces.

Democratic leaders, who are in the minority in both chambers of Congress, have responded by trying to embarrass Republicans into taking a bipartisan approach. The incoming Senate minority leader, Senator Charles Schumer of New York, called it “stunning and not surprising” that the CIA should charge Russia with trying to elect Mr Trump. “That any country could be meddling in our elections should shake both political parties to their core,” Mr Schumer said in a statement. Others have thanked Mr Obama for ordering an investigation into what is known about Russian meddling, and expressed hopes that as much as possible of the probe would be made public before the presidential inauguration on January 20th.

The reasons for this partisan stand-off are not mysterious. For starters, the next president has declared that the allegations of Russian hacking are simply unproven, and launched an attack on the credibility of the intelligence agencies that he will soon command without obvious precedent. Interviewed recently by Time magazine, Mr Trump said of the hacking: “It could be Russia. And it could be China. And it could be some guy in his home in New Jersey.” Asked about his desire for a reset of relations with Mr Putin—ie, precisely the strategy held against Mr Obama by Republicans—Mr Trump is unapologetic. “Why not get along with Russia?” he asked Time. The Russians are “effective” and “can help us fight ISIS.”

Still more remarkably, a statement from the Trump transition office mocked American intelligence agencies, saying: “These are the same people that said Saddam Hussein had weapons of mass destruction.” The official statement declared that the election is now over and it is time to “move on.”

As a result, congressional Republicans are stuck. They have long dreamed of unified government, in which they control both chambers of Congress and the White House, so that they can advance the sort of conservative programme that they believe will set the country on the right course. Smart and candid Republicans always conceded in private that securing the White House was hard because core elements of their programme—eg, cutting taxes for big corporations and slashing regulations—are not very popular. Now they have found a populist standard-bearer who has an astonishing ability to speak to working-class voters, notably whites living in bleak Rust Belt states, and to carry them into power on his coat-tails. Many elements of Mr Trump’s policies make thoughtful Republicans queasy to the point of misery, from his fondness for Mr Putin to his willingness to pick up the telephone and bully company bosses into keeping specific factory jobs in America, as if he were a Gaullist French president rather than leader of a free-market democracy. But many millions of those Mr Trump brought into the party are Trump voters more than they are Republicans, and they frighten and cow members of the party that he has captured.

Talk of Russian hacking puts Republicans in one last bind. Many senior figures on Capitol Hill distrust Mr Putin. But they know that grassroots conservatives see much to like in a Russian-style approach to fighting Islamic terrorism, if that means an unsqueamish willingness to back secular autocrats in the Middle East, and attack targets in Syria with ruthless indifference as to who is underneath. Mr Trump is clearly tempted to do a deal with Mr Putin in which America applauds as Russian warplanes carry out the Trumpian campaign promise to “bomb the shit out of ISIS”, with little thought for collateral damage. The bet in Trump Tower is that the other side of any such deal, perhaps involving the lifting of sanctions on Russia or a promise not to back any further enlargement of NATO, will be greeted by the American public with a yawn.

The hacking row is not quite over. As Lexington writes this posting, aboard an American military transport plane into Baghdad with the Defence Secretary, Ashton Carter, it seems likely that Mr Trump is about to name as his secretary of state Rex Tillerson, the chief executive of Exxon Mobil, the oil company. Mr Tillerson is as close to Mr Putin as any American businessman, even being decorated with Russia’s Order of Friendship.

Expect those links to come up in Mr Tillerson’s confirmation hearing. Senator Lindsey Graham of South Carolina, a Republican and a Russia hawk, told the Post: “Let’s put it this way: If you received an award from the Kremlin, order of friendship, then we’re gonna have some talkin’. We’ll have some questions.” Mr Trump will be counting on the narrow Republican majority in the Senate to defer to his right to nominate who he chooses to the cabinet, after a bit of theatrics in the committee room.

Some may wonder if this latest squabble matters. There is no evidence of actual collusion between Mr Trump and Russia. Mr Putin’s fierce dislike of Mrs Clinton, who as secretary of state questioned the validity of the 2011 elections in Russia, is more than enough motive to want her defeated. It is unknowable whether the last-minute leaks of Democratic e-mails affected the result. Most straightforwardly, a close election is over and Democratic leaders are not questioning the result.

This squabble does matter. When the next president of America takes his oath of office in January, officers of Russian intelligence can savour a historic win. And that astonishing, appalling fact has divided, not united, the two parties that run the world’s great democracy. That should be enough to unsettle anyone.