The deeply divisive issues of race and immigration have been forced onto Ireland’s political agenda, and there will be no escaping the debate that will unfold in the run-up to the next general election. It is, in truth, a debate that has been waiting to happen. Immigration has been a remarkable feature of Ireland’s recent economic performance, with tens of thousands of workers from eastern Europe arriving in the country to seek work in Europe’s most dynamic economy.

There are now at least 166,000 migrant workers living in the state, and possibly more than 200,000, with thousands more arriving each month to take jobs that would otherwise not be filled. Ireland’s economy is as close to full employment as it can get, and without the steady influx of migrants growth would stall.

The visible effects of immigration can be seen around the country, as Polish shops spring up in even the smallest of towns, foreign registered cars fill the roads and foreign accents start to dominate service industries. Social tension, so far, has been rare. Ireland’s immigrants tend to be hard-working, ambitious and come from cultural and social backgrounds that should ease assimilation.

Ignorance and fear, however, are never far below the surface in any society and are easily stoked, particularly when politicians fail to have the courage to lead. When Ireland, along with Britain and Sweden, decided not to impose restrictions on immigration from the 10 new accession states of the European Union, it made the right choice. It was both pragmatic and morally sound.

Ireland’s economy needed the workers those countries could provide and, as one of the great beneficiaries of EU membership, Ireland was not prepared to deprive new members of the opportunities that it had enjoyed. Yet at the time, instead of making a strong case for immigration and convincing the Irish people of its merits, politicians from all the main parties chose to pretend large-scale immigration would not happen and demonised as racists those who suggested it would.

Now the wheel has turned. Ireland’s trade union movement and the Labour party have started to dabble with policies that appear designed to exploit fears and play to the lowest common denominator. Pat Rabbitte, the leader of the Labour party, has raised the spectre of millions of Poles coming to Ireland’s shores. David Begg, the trade union leader, has spoken of a labour market of 2m people being “open to one of potentially 200m”. He and his union colleagues have put immigrants at the heart of union policy.

Their mantra is job displacement, their message clear: immigrants are taking Irish jobs and putting people out of work. Their solution, like Mr Rabbitte’s, is restrictions on labour mobility, in other words, keeping immigrants out.

Last week Fine Gael joined the debate with its own disingenuous wheeze, claiming immigrants entitled to Ireland’s generous child benefit schemes would take up to €150m out of the country each year. The party plucked the figures out of the air, and quickly reduced them, but the damage was done. Unsurprisingly, in the light of this, Irish attitudes are hardening. A recent poll suggested four-fifths of people believe immigration from the accession states should be restricted.

Michael McDowell, the minister for justice, was right last week when he attacked the Labour party for being “opportunistic, inconsistent, hypocritical, untrustworthy, incompetent, xenophobic and cynical” about immigration. It is a charge that can be levelled equally against the trade unions.

The genie is now out of the bottle, and there is no going back. Immigration and race will be significant issues in the next general election, and the political parties must not hide from them. They must instead engage the debate with rationality and challenge, like Mr McDowell has done, the insidious creep towards xenophobia that has been set on its way by the trade union movement.

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