ODD as it may seem, when Bob Corker, the Republican chairman of the Senate Foreign Relations Committee, said that he worries that Donald Trump approaches his job like a “reality show” and may set America on “the path to World War III”, he was not voicing the fear that causes Republican senators to lose most sleep. True, thoughtful Republicans really do worry that the president seems not to care if the world places more weight on his words than he does. Figures close to Mr Trump describe a man more interested in being seen to win, than in picking fights wisely. But most cling to the same hope that Mr Corker has now voiced in public: namely, that such “good guys” as the defence secretary, James Mattis, the White House chief of staff, John Kelly, and the secretary of state, Rex Tillerson, will be “able to talk [Mr Trump] down” if he “gets spun up”.

In the short term leading Republicans fear something less apocalyptic but more plausible: that Mr Trump is so thin-skinned, vindictive and bored by detail, and his party so divided, that Republicans may pass no substantial laws between now and the mid-term elections of November 2018. Two particular ambitions unite the squabbling factions of the Republican Party: fulfilling a long-standing promise to repeal and replace the Obamacare health law, and passing a comprehensive tax reform. In private, grandees put the chances of a full Obamacare repeal and replacement in the near future at close to zero. The chances of passing tax reform tend to be put at between 50-50 and zero. When asked point-blank what major legislative achievements are possible by November 2018, a surprising number wince and reply: maybe none. If that is the case, Republican bigwigs do not rule out losing the House of Representatives in a mid-term wave (the Senate map in 2018 so favours Republicans that few can imagine control falling to Democrats).

House Republicans tend to be more bullish about their chances. In part that reflects electoral mathematics. Most House members come from such conservative seats that they cannot win re-election—and certainly cannot survive the primary election that will choose the Republican candidate for their seat—without strong backing from diehard Trump voters. There are also more alternative-fact-loving blowhards in the House. In contrast, to win statewide races many Republican senators need both Trump loyalists and some Trump sceptics.

The real import of the Corker-Trump spat, carried out via duelling interviews and tweets, is larger than a loss of trust between an important committee chairman and his president, though that breach will itself have consequences. From the chair of the Foreign Relations Committee Mr Corker will have sway over what happens next with Iran, and the possible reimposition of American sanctions on that country. Mr Corker, a deficit-loathing fiscal hawk, also sits on the Budget Committee—a point that the Senate majority leader, Mitch McConnell, made this week, in an implicit warning to Mr Trump that calling Mr Corker a fool and mocking his height might not help pass tax reform. Mr Corker is an unusually liberated man. After two terms representing Tennessee, he is not standing for re-election in 2018.

The larger lesson is that Republicans, especially in the Senate, see a non-trivial chance that Mr Trump’s will be a failed presidency. Trump loyalists will scoff that Washington swamp-dwellers are merely thrashing about as their habitat is drained by a populist hero. But Republican leaders do not complain about Mr Trump making them do things that they resent, in the name of the people. Instead it is shockingly normal to hear prominent Republicans compare Mr Trump to a child with attention-deficit disorder, or describe a president who telephones to talk policy but seems not to understand bills being discussed, or wastes ten minutes on gossip. They share tales of Mr Trump losing votes because he bullies senators, or humiliates them in front of their peers. Republicans also know that, for all Mr Trump’s boasts about bipartisan dealmaking, it is in Democrats’ interests to see him fail. With few exceptions, Senate Republicans dislike Mr Trump. They increasingly worry that he will drag them down.