Under Fire, Powell Receives Support From White HouseBy STEVEN R. WEISMAN ASHINGTON, April 23 — Since the end of the war in Iraq, Secretary of State Colin L. Powell has come under intense fire from conservatives within the administration, in Congress and at policy institutes long favoring less diplomacy and more muscle in the American approach to the world. On issues from the Middle East to North Korea to the makeup of a postwar government in Iraq, Mr. Powell and the State Department have been battling hard-liners at the Pentagon and in Vice President Dick Cheney's office, administration officials say.In...