Agence France-Presse: The United States should not impose a cap-and-trade system to battle climate change this year because it amounts to a painful tax during a deep recession, senators argued Wednesday. “Now is not the time to put a national sales tax on every electric bill and every gasoline purchase,” Republican Senator Lamar Alexander, who sits on the Senate Environment and Public Works Committee, told reporters. “I’m open, as are several Republicans, to cap-and-trade, but it’s getting …