Immigration has emerged as a key battleground in the European Union referendum campaign. This could have worrying consequences for peace and stability in the multiracial and multicultural society that Britain has become. There is a sense among the leaders of the Leave campaign that most of the other arguments they have advanced are beginning to look less convincing. In particular the (much disputed) Treasury forecast that an average family could expect to be £4,300 worse off if Britain left the EU has dampened their more optimistic claims of unbounded growth and prosperity. Then President Barack Obama delivered a stark warning that a Britain outside the EU would be at the back of the queue for a new trade deal with the United States, suggesting that British exit (“Brexit”) would seriously damage British trade and industry. His claims were disputed, but they have had an effect.