Barack Obama: “We cannot go back to business as usual.”

It is a basic principle of American democracy that the government can’t selectively target individuals simply because of their political beliefs or what they say.

People need to “rediscover what’s the story we tell about how we’re going to live together, and see each other, and recognise each other, and disagree, and yet, still care for each other”.

When we choose, when we make that decision, I do believe – and there is evidence for this – that the world gets incrementally better, and that is a worthy goal and it’s worth fighting for.

The effort, he said, “should outrage all Americans, regardless of how they feel about Congresswoman Omar’s political views.”