On Tuesday morning, President Biden took to the podium at the White House to deliver a solemn and provocative speech. As punishment for waging war on Ukraine, he announced,  the United States would cut off Russian oil imports. Mr. Biden said the move would require some sacrifice, but would be for the greater good. How much will the ban hurt Russia, and American consumers? Guest: Clifford Krauss, a national energy business correspondent for The New York Times.