The U.S. Pentagon is investigating a new military command structure for North America that could mean far reaching changes for security in the United States and Canada.

For more than 40 years NORAD has been the continent's joint military command for air defence and has integrated the U.S. and Canadian armed forces.

Two hundred and eighty Canadians operate on U.S. soils, about 50 American military personnel are based in Canada. But the Pentagon is now looking at a new structure that could affect all aspects of homeland security: air, land and sea.

Jill Sinclair

A top Canadian commander told a Parliamentary committee that both the Canadian and American military are already discussing greater co-operation. "There is an opportunity her for us to recognize our mutual concerns about continental security," said Lt.-Gen. George MacDonald. "Not only aerospace related, but land and sea related."

A top foreign affairs official conceded that U.S. plans could have an impact on Canadian sovereignty.

"When they talk about things like a new command structure there are implications for Canada," said Foreign Affairs Department spokeswoman Jill Sinclair.

"When you start talking about things that impinge on NORAD, hey, we're you're partner. We have a treaty relationship here. It matters to us here."

The Canadian military has already increased its interdependence with the U.S. recently. A Canadian naval task force and some ground troops are already operating with U.S. forces in Afghanistan.

At home, there have been 10,000 air patrols over North American air space since Sept. 11, carried out by both countries under NORAD. And the military doesn't rule out a greater exchange of troops between Canada and the U.S. in the name of mutual security.

"There is a possibility that we would augment our exchange of personnel on both sides of the border. But that would have to be seen through any discussion that we have with the Americans," said Lt.-Gen. MacDonald.

Critics say Canada seems too willing to give up its independence in the rush to satisfy American security concerns.

"There's a real danger here that the government is failing to see that an essential part of security, from the Canadian point of view, is preserving Canadian sovereignty," said the NDP's Bill Blaikie.

"We are not going to give up one ounce of sovereignty," said Defence Minister Art Eggleton. "There's nothing wrong with two sovereign nations looking to co-operate for their mutual benefit."

Senior government officials acknowledge Canada may well give up "some" sovereignty by further integrating with the U.S. military. But they worry that the alternative might be worse: to have the U.S. act on its own, putting NORAD or any new command structure for North America strictly under U.S. control.