PITTSBURGH (Reuters) - Democratic presidential challenger John Kerry (news - web sites), lashing out at the White House's "twisted sense of ethics and morality," accused Republicans on Friday of distorting his record and attacking his patriotism. Kerry, at an outdoor rally on the University of Pittsburgh campus, used an American flag and the national anthem to fire back at Republicans who charge he is weak on defense for voting against some weapons systems and an $87 billion bill to pay for operations in Iraq (news - web sites) and Afghanistan (news - web sites). Kerry, a decorated Vietnam War veteran,...