"The enlargement of the EU and the free movement of people are both fine ideas. But, taken together, they have changed the nature of the union. A pragmatic pro-European should acknowledge that, when circumstances alter, democratic systems adapt. Changes to the welfare rules – allowing countries more scope to give priority to their own citizens – would make it easier to win the more important argument for open borders."
In theory, David Cameron and Radoslaw Sikorski should get on marvellously. Both the British prime minister and the Polish foreign secretary studied at Oxford and were members of the elite Bullingdon club, which specialises in dressing up, drinking, vomiting and vandalism. Both men have matured into robust conservatives. But last week we witnessed an unedifying dispute between the two politicians, sparked by Mr Cameron's suggestion that Britain should not be paying child benefit to children living in Poland, even if their parents are working in Britain. In response, Mr Sikorski accused the British of stigmatising Polish immigrants and tweeted (in Polish) a suggestion that Poles in Britain should return home.
Neither Mr Cameron nor Mr Sikorski come out of this dispute unblemished. It is graceless for the prime minister to suggest that Britain made a "huge mistake" by letting in hundreds of thousands of immigrants from Poland – without also stressing that the Poles have generally made a big contribution to British society, working hard, paying taxes, starting businesses and adding to the vibrancy of the country. On the other hand, Mr Sikorski could temper his urge to stick up for his fellow countrymen with an acknowledgment that many Poles, including him, have benefited from the welcome extended to them in Britain.