Republican senators sent the White House a sharp message on Tuesday, warning that they were opposed to President Trump’s plans to impose tariffs on Mexican imports, just hours after the president said lawmakers would be “foolish” to try to stop him....“I want you to take a message back” to the White House, Senator Ted Cruz, Republican of Texas, told the attorneys, according to people familiar with the meeting. “You didn’t hear a single yes” from the Republican conference. He called the proposed tariffs a $30 billion tax hike on Texans.