James Naughtie argues that a common American identity will be achieved - one day - despite the heightened political rhetoric around immigration, that is making it one of the most contentious issues in this year's presidential election.

He recalls Ronald Reagan's 'homely evocation of an American character'. For Reagan, James says, the inscription on the Statue of Liberty, 'give me your tired, your poor, your huddled masses', had real contemporary power.

For many Republicans today, he says, it's a very different story.

But he sees signs of change. On a recent visit to the US border in Arizona, he met a 'cattleman of resolute conservative views in his 80s', who tells James that although he's fed up with armed drug runners using his land, he believes most people cutting through the fence are 'good people, in search of new lives'.

'The huddled masses will be absorbed... eventually', James writes. 'But the question right now is how much damage will be done in getting there - to the principles of their democracy, and perhaps to their precious belief in themselves.'

Producer: Adele Armstrong