Few tears were shed for the plight of Tory MP Adam Holloway on Monday. He complained that he couldn't get a haircut last week because his refugee barber had gone on holiday to the country from which he fled; damned inconvenient.

This struck many MPs as somewhat lacking in taste, only a week after the country had been shocked by the sight of a refugee toddler lying dead on a beach. But Mr Holloway inadvertently put his finger on a central issue in the whole “migration crisis”.

We need more migrants. Britain is largely a service economy and becoming ever more so. It's not just immigrant hairdressers we need but carers of all kinds. As Britain grows older, despite a recent increase in the UK birth rate (largely from immigrant families), we need many more immigrants than the 160,000 the EU commission chief, Jean Claude Juncker, called for in his State of the Union speech yesterday.

Indeed, only last year, the UK Treasury said Scotland alone would need 500,000 immigrants over the next 20 years just to keep the same balance of pensioners to working age adults as the rest of the UK. And the UK's dependency ratio is rising fast also.

Professor David Bell, the economist, spelled out the fiscal implications of this in an article for the Centre for Constitutional Change this week. I paraphrase, but there isn't a cat in hell's chance of Scotland being able to support this ageing cohort with the present dwindling band of young workers.

Under the Scotland Bill proposals, this country is to be landed with the responsibility of financing much of its welfare budget, most of which goes on elderly care. The Barnett formula is being phased out. So it is going to require a many more taxpayers (or much higher taxes) to keep pace with demands on the system.

Most European governments are in the same position, though they tend to keep quiet about it. Mr Juncker alluded to it yesterday; cautiously, as this demographic challenge has spawned a new kind of anti-German paranoia.

On the Tory benches at Westminster, and in the cabinet of Hungarian prime minister Viktor Orban, there is a conspiracy theory. It is that Germany – which has the most rapidly ageing population in Europe – is welcoming all those refugees for economic gain.

According to the BBC's Robert Peston, the German government has realised that, by 2060, there will be fewer than two workers generating taxes for every citizen over 65. Ms Merkel hopes an influx of young able-bodied, and generally skilled, migrants could cut the dependency ratio significantly.

Their efforts will help to boost Germany's already world-beating export industries, and provide carers for the widowed Schwabian Hausfrau of the future. A fiendish plot if ever there was one!

But there's no conspiracy regardless of what Nigel Farage may think. Germany has made no secret of its openness, and it isn't for narrow economic motives.

Rather, the economic motives in this instance happen to coincide with the humanitarian instincts of a country that still suffers the guilt of having been largely responsible for Europe's last greatest refugee crisis: the Second World War.

Nationalist politicians in many European countries (though not, thankfully, in Scotland) loath this economic approach to immigration. Mr Orban says the refugee crisis isn't about economics but culture. “Those arriving have been raised in another religion and represent a radically different culture, the Muslim”, he says.

Mr Orban says that resisting immigration is about “preserving European Christian civilisation”. He is under pressure from the Hungarian far right (yes there are people further right than him). The aptly named Jobbik party wants even tougher action against immigrants than razor-wire fences and curfews.

Of course, the EU is often cited, or used to be before the Greek crisis, as the pinnacle of European civilisation: a voluntary union of nations bound by a common commitment to freedom, prosperity and the rule of law. And it was to this tradition that Mr Juncker appealed yesterday.

He didn't duck the culture question either, but put it in perspective. “There is a reason the number of O’Neills and Murphys living in the US exceeds the number in Ireland”, he said pointedly.

The Ukip leader, Nigel Farage, almost visible blanched at the thought of there being more Muhammads and Husseins in Europe than in the Middle East, though he needn't worry about Britain since we have opted out of Mr Juncker's “compulsory” scheme for refugee distribution.

This leaves us doubly damned: morally and economically. It is a wretched position for Britain to be in, offering only 20,000 places for Syrian refugees over five years. We are becoming the pariahs of Europe,with a reputation for being petty minded, insular, ignorant of world affairs.

After all, the four million who have been displaced from Syria and Libya have left after civil wars in which we played a significant role. Britain supported the rebellion against the Assad regime in Syria in 2012 which unfortunately turned into Islamic State.

We acted as unconscious midwives to Islamic extremism when we bombed Muammar Gadaffi's army in Libya in 2011. There may have been good reasons for these interventions. But the first rule of foreign military involvement is: if you break it you mend it.

We can't pretend that these conflicts are in far away countries of which we know nothing. We are fighting against Islamic State. How can we refuse refugees from the conflict?

Going further back, we share responsibility for creating the circumstances in which al Qaeda, which begat Islamic State, emerged from the wreckage of the invasion of Iraq in 2003.

No, we didn't actually create these murderous fanatics but, as the former Deputy Prime Minister, Nick Clegg, has said, we cannot “airbrush away” our involvement. There was no al Qaeda in Iraq before we broke down the door.

So, of all European countries (most like France rejected the Iraq war), Britain cannot shirk responsibility for the chaos in the Middle East. Yet we refuse to take even our share of the 160,000 refugees from these conflicts.

We're full; being swarmed; can't take any more.

Tell that to countries such as Jordan, population 6.5 million, which has absorbed more than one million; or Lebanon, where one in five of the population is a refugee; or Turkey, where dead refugee children wash up on the beaches.

But perhaps the worst thing about Britain’s buck-passing on the refugee crisis is that it is economically illiterate. As Mr Juncker says, there is a reason why America took so many of the “the huddled masses yearning to be free”. It made damned good economics.

Like Germany today, America welcomed the highly motivated and relatively prosperous (they could afford the passage) refugees from Eastern European pogroms. They helped build the greatest economic power on the planet.

If Germany is doing the same today, by absorbing 800,000 of these refugees, then we can only say; good luck, Ms Merkel. Sometimes doing the right thing brings the best rewards. If only we could see where our own interest truly lies.