Among the letters I have received from new members -- 10,000 have joined the Liberal Democrats in the wake of the referendum -- was one saying this:

“I can‘t believe just how stupid I’ve been, sorry doesn’t really cover the hurt my part has caused more than 16 million residents of our great country. Please save the union between the United Kingdom and Europe.”

Buyers’ remorse after the vote to leave the European Union seems widespread. But I don’t blame those who were duped. I blame those who knowingly made undeliverable promises. Voters had barely returned home from the polls before “leave” leaders announced there would not be an extra 350 million pounds ($465 million) a week to spend on the National Health Service, despite the claims plastered on the side of their battle bus. Promises to cut immigration have been similarly abandoned.

But the really big whoppers have yet to be revealed to voters. Boris Johnson promised that Brexit would create 300,000 jobs. But other than Whitehall scurrying to recruit an army of bureaucrats to haggle over emergency trade deals in the coming years, the only talk in the labor market is of job losses.

And then we have the really big lie: that somehow Britain would be able to reduce free movement from Europe but remain in the single market. Perhaps whoever inherits the title of prime minister (or should that be poisoned chalice?) will pull off a spectacular negotiating coup, but I’m not holding my breath. More ambitiously still, the “leave” campaign suggested we will be able to strike a deal that restricts EU immigration to Britain but leaves Britons free to live and work on the continent. Again, don’t hold your breath.

It is now clear there is absolutely no Brexit plan, either from those who have schemed all of their political lives for this moment, or from George Osborne, who claims it is not his responsibility, even though he remains chancellor of the exchequer (for now at least). The Conservatives have put a bomb under the economy, destroying their reputation for economic competence. That is their problem; but since David Cameron announced his resignation, there has been a massive vacuum at the heart of the British state. Both the Conservatives and the Labour Party risk descending into civil war as they fight their respective leadership campaigns.

This puts responsibility on the Liberal Democrats to fight for our European future. There is particular frustration among young people, 73 percent of whom voted “remain,” and we must give voice to them. There was already scandalous generational unfairness in Britain. All young people are asking for is economic competence, a government prepared to tackle international challenges with international solutions, and some of the opportunities that were enjoyed by the baby-boom generation; those are reasonable demands.

I was really struck by the mood of optimism, openness and determination at a massive rally I addressed this week in Trafalgar Square. Many of those attending were young and concerned for their future -- chanting “EU, EU, EU” with passion and fervor. Truly, we live in extraordinary times.

These are the people we politicians must fight for. Meanwhile, I have been in Brussels to urge understanding on European leaders furious with the market turmoil unleashed in their economies by Brexit. And I‘m urging the government to pump funds into the British Business Bank to ensure liquidity.

Britain’s overriding priority now must be to remain in the single market, to head off a major recession that will destroy jobs and livelihoods. No matter what the outcome of the bloody leadership battles in the Conservative and Labour parties, the Liberal Democrats will be the only party fighting the next election fully committed to maintain the best possible relations with Europe. Bring it on.

By Tim Farron

Tim Farron is the leader of Britain’s Liberal Democrat Party and the member of Parliament for Westmorland and Lonsdale. --Ed.

(Bloomberg)