Barack Obama: “As long as I'm President, America is going to pursue an all-of-the-above energy strategy.”

I think when we act on that basis, it doesn't always work out, but over time things do get better.

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”.

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

Because if this becomes the new normal, there’s no reason to believe it will stop with her — or that future presidents, in either party, won’t do the same.