When the phrase “think of the children” gets wheeled out in political debates the best advice for children is to check their wallets.

“I want my children – and their children – to be able to play on a day out in the North Downs near London” said David Cameron last year, as the Prime Minister pledged to protect the Green Belt from development.

But making this arbitrary swath of area around UK towns and cities (some of it unlovely scrubland) automatically off-limits to construction puts a limit on house building. And that pushes up house prices, which, in turn, means many young people are today unable to afford homes of their own. It will likely be even worse in future unless planning controls are loosened.

“The British economy will stay on course and we will not burden our children and grandchildren” trumpeted George Osborne in March as he stuck to his plan to run an absolute budget surplus by 2020 and every year thereafter.

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But excessive zeal by politicians such as the Chancellor to reduce government borrowing and the national debt in the near term merely weakens the economy, which makes life painful for young people entering the job market. Those in their 20s suffered easily the largest hit to their incomes of any age group in the years following the 2008 crash. Excessive austerity compounded this suffering.

And cutting expenditure on infrastructure projects – which is where Mr Osborne found much of his budget savings in the last Parliament and which is the implication of his foolish failure to carve out state capital spending from his annual budget surplus target – will mean crumbling infrastructure and a less productive national economy. And that will mean lower incomes for our children.

So here we have two policies – green belt protection and fiscal austerity – dressed up by politicians as protection for the young, but which actually end up hurting the interests of that group.

And now we have Brexit. “We must seize this chance, this opportunity to take [our country] back” urged Nigel Farage earlier this month. And then the inevitable kicker from the Ukip leader: “After all, what sort of future do we wish to leave our children and grandchildren?”

6 ways Britain leaving the EU will affect you Show all 6 1 /6 6 ways Britain leaving the EU will affect you 6 ways Britain leaving the EU will affect you More expensive foreign holidays The first practical effect of a vote to Leave is that the pound will be worth less abroad, meaning foreign holidays will cost us more nito100 6 ways Britain leaving the EU will affect you No immediate change in immigration status The Prime Minister will have to address other immediate concerns. He is likely to reassure nationals of other EU countries living in the UK that their status is unchanged. That is what the Leave campaign has said, so, even after the Brexit negotiations are complete, those who are already in the UK would be allowed to stay Getty 6 ways Britain leaving the EU will affect you Higher inflation A lower pound means that imports would become more expensive. This is likely to mean the return of inflation – a phenomenon with which many of us are unfamiliar because prices have been stable for so long, rising at no more than about 2 per cent a year. The effect may probably not be particularly noticeable in the first few months. At first price rises would be confined to imported goods – food and clothes being the most obvious – but inflation has a tendency to spread and to gain its own momentum AFP/Getty Images 6 ways Britain leaving the EU will affect you Interest rates might rise The trouble with inflation is that the Bank of England has a legal obligation to keep it as close to 2 per cent a year as possible. If a fall in the pound threatens to push prices up faster than this, the Bank will raise interest rates. This acts against inflation in three ways. First, it makes the pound more attractive, because deposits in pounds will earn higher interest. Second, it reduces demand by putting up the cost of borrowing, and especially by taking larger mortgage payments out of the economy. Third, it makes it more expensive for businesses to borrow to expand output Getty 6 ways Britain leaving the EU will affect you Did somebody say recession? Mr Carney, the Treasury and a range of international economists have warned about this. Many Leave voters appear not to have believed them, or to think that they are exaggerating small, long-term effects. But there is no doubt that the Leave vote is a negative shock to the economy. This is because it changes expectations about the economy’s future performance. Even though Britain is not actually be leaving the EU for at least two years, companies and investors will start to move money out of Britain, or to scale back plans for expansion, because they are less confident about what would happen after 2018 AFP/Getty Images 6 ways Britain leaving the EU will affect you And we wouldn’t even get our money back All this will be happening while the Prime Minister, whoever he or she is, is negotiating the terms of our future access to the EU single market. In the meantime, our trade with the EU would be unaffected, except that companies elsewhere in the EU may be less interested in buying from us or selling to us, expecting tariff barriers to go up in two years’ time. Whoever the Chancellor is, he or she may feel the need to bring in a new Budget Getty Images

Well, the answer is that young people are now facing a future where they cannot work, travel and study freely across the 27 other countries of the European Union in the manner of their parents’ generation.

According to the vast majority of credible economic forecasts, Brexit also means a smaller UK economy than otherwise by the end of the next decade, so smaller incomes for families in the future. Brexit will make future generations poorer than they otherwise would be.

Yes, one could point to countervailing benefits in all three cases: a more expansive green belt, a smaller national debt and more modest annual state interest payments, no more annual contributions to the EU budget and greater nominal “control” for Westminster.

We all have our individual preferences in life. But it’s unlikely that the majority of younger generations would choose the trade-offs on these issues that are effectively being made on their behalf. And, of course, on the European Union we can say that with some confidence because roughly 75 per cent of those aged between 18 and 24 are believed to have registered a “remain” vote.

The economics of inter-generational equity can be complex. One of the major battlegrounds in the young versus old debate has been the cross-party supported “triple lock” on annual increases in the state pension.

In theory, higher state pensions should, eventually, benefit everyone – old and young alike. After all, today’s young are not some kind of Peter Pan generation. Hard as it might be for some of them to believe, they will also one day have a free bus pass in their grip.

Their problem lies in the sustainability of financial commitments to pensioners. As the economist Herbert Stein put it: “If something cannot go on forever, it will stop”. If it is unsustainable to maintain that level of generosity to all over 65s then such benefits will, inevitably, at some stage, be diminished. And that means the current generation of lucky pensioners will have effectively extracted resources from generations in work today.

Tuition fees can be viewed in this sustainability context. It was politically and economically unsustainable to massively increase the number of young people going through higher education in the 1990s and 2000s while continuing to fund universities entirely through general taxation. That is why the introduction of fees was, sadly, necessary.

Politicians can and should attempt some level of redistribution to compensate generations that lose out, though, from such shifts. This is hard. Changes in the shape of an economy and developments in technology will drive both opportunities and outcomes across the generations – and these are inherently hard to predict.

But this isn’t an excuse for not trying. Certain demographic trends are well established. It is no secret that the present level of generosity when it comes to pensioner benefits will not be sustainable in the long run. On that basis they should be trimmed today and more resources spent on enhancing economic opportunities for the young, especially given the disproportionate pain suffered by the under 30s in the years after the great crash. The threatened economic pain from Brexit merely adds to that imperative. The over 50s voted for Brexit, so they must not, as a group, be allowed to push the cost entirely onto others.

The threat of climate change is another area where the expert scientific advice is entirely clear. The case for major action today to curb carbon emissions for the economic well-being of future generations has been clear cut since Sir Nicholas Stern’s landmark report a decade ago.

Yet so often, instead of honest attempts at maintaining intergenerational equity from politicians, we see a cynical pandering to the narrow interests of older generations; accompanied by buckets of crocodile tears for the prospects of the young.