A new poll released Saturday showed nearly half of all Americans believe Oliver North should stand trial on charges stemming from the Iran-Contra affair but should be pardoned by President Bush if convicted. U.S. News & World Report said 1,004 adults were asked if the former Marine should be sent to prison or pardoned by Bush if he was convicted of obstructing a congressional and presidential investigation, making false statements to Congress and destroying official government documents. The magazine said 49 percent of those questioned in the national survey said Bush should pardon North, while 37 percent said he should be sent to prison. Another 14 percent did not know or refused to answer.