Because as long as the Democrats control the senate it would be a wasted effort. Even if we had enough Republicans with a spine(which I seriously doubt) to Impeach him in the House, it would go nowhere. Just like when they impeached Clinton. That time WE controlled BOTH Houses, but the Republicans IN THE SENATE WERE TOO F'ING SPINELESS TO CONVICT AND REMOVE HIM FROM OFFICE. IN FACT it was their spinelessness that the Dems used to help re-elect Clinton in 1996.