Colombian union organizer Luis Adolfo Cardona narrowly escaped torture and certain assassination, after witnessing the murder of another union leader in 1996. Now he's touring the U.S., hoping to inspire support for Colombia's workers as they struggle against the Coca-Cola Company and its bottlers in that country. ÒIn Colombia, we have great social problems,Ó Cardona told an attentive audience at Loyola University early Thursday night. But thereÕs one problem I want to talk about most: the role of the multinational corporations and the government.Ó