We live in a time when words have never meant less and cynicism has never been more widely accepted. Did I say “accepted”? That is too weak. The embrace of dishonesty is so clammy, politicians react with astonishment when naive citizens demonstrate their bad taste by supposing that they are somehow accountable for their actions.

In near identical language, Amber Rudd said she was “surprised” that the Tories’ “hostile environment” for migrants had led to the state persecution of the innocent. Her contemporary Emily Thornberry was not just “surprised”, she was “really shocked” that racists were thanking her for the fine job she and her colleagues in Jeremy Corbyn’s Labour party were doing in baiting Jews.

The personal is no longer political. In private, Thornberry and Rudd are forceful, friendly, intelligent and liberal. To use a phrase that falls from our lips too easily, they “don’t have a racist bone in their bodies” and appear genuinely outraged when their critics assume they are built with little else. They don’t understand that racist bones are neither here nor there when what they lack are backbones.

After Ukip terrified the established parties, politicians on the make resolved to show their hostility to migrants. Rudd made the smart move of closing her eyes and blocking her ears as British citizens complained that the state was forcing them to produce documentation going back decades to rent a home, open a bank account, go to a doctor or hold on to a job.

What did you expect her to do? Challenge the prime minister and take on the Tory backbenches and Tory press by creating a “just environment” for migrants? Come now. Conventional wisdom holds we should nod along and realise she had no choice. Not because Rudd is wicked, but because no one on the right can be liberal on immigration in the 2010s. It’s not personal, just political.

As with Ukip, so with the Corbyn insurgency. Thornberry does not get on in his Labour party by showing solidarity with abused Jewish colleagues. She gets on by pleasing Vladimir Putin’s propagandists and announcing in defiance of all evidence that the United Nations, not Russia, was stopping chemical weapons inspectors investigating the gassing of civilians by the Kremlin’s Syrian ally. Once again we are meant to shrug. Wake up and smell the bitter coffee. This is how an ambitious Labour politician must behave if they want to appeal to Len McCluskey and all Labour’s cranks and conspiracists who will have their say when the next leadership contest comes.

Rudd and Thornberry are mere appetisers. No historian can find a precedent for today’s parliament where the prime minister and most of the government and opposition benches will consciously vote for a policy they know will make the nation poorer. So complete is their abandonment of any conception of political integrity that they cannot tell the truth about the choices they are making as they push to leave the single market. They will not level with the public and say suffering is the price of a hard Brexit. In the words of the anti-Brexit campaigner Hugo Dixon, it would be an “electrifying moment” if Theresa May or any one of her ministers merely gave a plain account of the country’s future.

If it’s not a constant of human nature to damn the present and romanticise the past, it’s certainly a constant of journalism. Hans Rosling and Steven Pinker have written with penetration on how, with the ominous exceptions of the environment and the human race’s mass extinction of species, life is becoming better. Whether you measure global poverty, access to healthcare, sexual equality, the experience of war and violence or life expectancy, the present is preferable to the recent past – overwhelmingly so.

It sounds like mere nostalgia to unleash a heartrending “O tempora! O mores!” and lament our ill luck to have fallen under the rule of a uniquely cynical generation of politicians. Few have ever got to the top of politics or any other hierarchical system without compromising their integrity, after all. What’s new? To my mind, there are two solid reasons for thinking the British at least are in a new and worse place .

The first is the difference in scale between the spin of the Hillary Clinton/David Cameron/Nick Clegg generation of politicians and bombast of today’s leaders. The Leave campaign won with barefaced lies: that Britain paid £350m a week to Brussels and Turkey was about to join the EU and send an invasion force of millions of (Muslim) migrants our way. Trump won by convincing tens of millions of Americans that the truth about him was fake news.

There are many honourable political exceptions and we can only hope they will be steeled by today’s battles and provide the leaders of the future. But when all the caveats are made, we are still left with politicians who have learned that the more vehemently they deny, the more they succeed; the greater the lie, the greater the reward.

Then there is a difference in the stakes, which could not be higher. The Tories may not end up as a nationalist party, which appeals only to whites. Labour may not end up as the natural home for creeps. But in both instances the fight is on and the outcome uncertain. Beyond them lies Brexit, the greatest issue since the Second World War. I suppose it is asking too much to expect Conservative and Labour leaders to adopt a Churchillian pose and promise “blood, toil, tears and sweat”. But their inability to acknowledge the pain ahead for the most vulnerable people and most depressed regions is to use the word in its proper context for once more than a surprise. It is “shocking”.

• Nick Cohen is an Observer columnist