The timing could not be worse.
The leaders of the Labour and Liberal Democratic parties are skipping a state banquet for the President. But they still have plenty on their plates. Labour MPs have been publicly chewing over the implications of coming third with 14.1 per cent of the vote in Britain's election for the European Parliament.
Labour's Emily Thornberry noted that Labour wasn't clear enough on its position on Brexit. Voters backed parties whose policy "could be summed up in one word or three words". She might have been thinking about the self-explanatory Brexit Party or the Liberal Democrats, whose slogan was "Bollocks to Brexit".
The Brexit Party topped the EU poll with 31.6 per cent. The Lib Dems, Britain's long-time third party, finished second with 20.3 per cent. Even the tiny Greens with 12.1 per cent came in fourth ahead of the Tories with 9.1 per cent.
Opinions evident in the EU election have spilled into polls on Westminster voting intentions. A YouGov poll showed that if a national election were held now, the Lib Dems would be the leading party with 24 per cent, the Brexit Party second with 22. An Opinium survey suggests that hundreds of Conservative seats are at risk from the Brexit Party, whose leader, Nigel Farage, wants a no-deal exit.
At the moment, this is a second coming for the Lib Dems after the party emerged from coalition with David Cameron's Conservatives severely weakened.
Labour, trying to fish in both Remain and Leave streams, ended up seeming muddled. "The problem with Labour's attempts so far to bridge these two groups is that it's ended up satisfying neither," said political analyst John Curtice. He says Tory supporters who decamped to the Brexit Party will only return if Britain leaves the EU.
Both the Tories and Labour can no longer risk a national election any time soon. A key barrier to reaching a Brexit deal is that Westminster is split between Remain, Leave with a deal and Leave with no-deal factions. Labour's remedy looks more obvious — take over the Remain flag from the Lib Dems.
Conventional wisdom is that the current realignment will not hold for long. Yet Brexit has carved up the electorate, crossing class and ideology and encouraging voters to flirt with chaos. The main parties are in serious difficulty.