"There is room for only one great power here, and everyone except the French recognizes who that is," said a representative of one Western Hemisphere nation.
McKinley toured the pavilions of other Western Hemisphere nations, attracting crowds and applause wherever he went.
The Bush administration is pushing for a free trade agreement that would include all of the Western Hemisphere nations.
Diplomats from 34 Western Hemisphere nations, including the United States, began a two-day conference to start drawing up a new security treaty.
Free trade is high on the agenda of the first summit meeting of Western Hemisphere nations in nearly three decades.
The study was presented earlier this month in Caracas, Venezuela, before a ministerial level meeting of delegations from Western Hemisphere nations.
The move left Argentina the only Western Hemisphere nation with delegates from Germany, Italy and Japan.
More than 6,500 athletes and officials are expected to descend on Indiana and 38 Western Hemisphere nations will be represented.
The meeting of 34 Western Hemisphere nations was supposed to seek ways to help tens of millions of poor people in the region.
But more than 100 nations are attending, including all other North Atlantic Treaty Organization members, and virtually every Western Hemisphere nation.