BUSH OFFICIALS SAY THE TIME HAS COME FOR ACTION ON IRAQ
Top national security officials in Bush administration say in near unison that Pres Saddam Hussein's efforts to build arsenal of immensely destructive weapons leaves US little choice but to act against Iraq; comments on Sunday television news programs by Vice Pres Dick Cheney, Defense Sec Donald Rumsfeld, national security adviser Condoleezza Rice, Sec of State Colin L Powell and Joint Chiefs of Staff chairman Gen Richard B Myers noted; photo (M)