The Democratic Party is using the threat of presidential impeachment to raise money. Its website warns that "Republicans have already held their first committee hearing on impeaching President Obama," and urges donors to protect the Democratic majority in the U.S. Senate. That's one way to stop impeachment. Here's a better way: Tell the president to obey the law. Putting the nation through the ordeal of impeachment would be drastic. But the framers of the Constitution designed impeachment to stop precisely what President Obama is doing — grabbing for more power than the Constitution allows. The nation has impeached a president...