Do people around the world have a right to move to the United States? It’s a bedrock belief of most conservatives that there is no such right. The U.S. sets its own immigration policy, admits whom it chooses, and foreign nationals in foreign countries have no right — a claim that could be pursued in court — to enter the United States.

Now, Hillary Clinton says there is such a right, at least if a tweet from her campaign headquarters can be taken for a policy pronouncement.