Canadian officials are expressing concern about President George W. Bush’s decision to build a national missile defense shield because missiles intercepted by the system could land in Canadian territory — perhaps even population centers.

The Calgary Herald newspaper reported yesterday that a recent Canadian military analysis concluded that the Pentagon likely would need little contribution from Canada in building the system.

However, the paper said, about the only thing Washington would require from Canada “is its airspace.”

“While NMD (national missile defense) does not require Canadian involvement — intercepts would occur over Canadian territory,” the paper said, quoting a Canadian Forces briefing paper written last year.

One U.S. analyst quoted by the paper said Canada may just have to live with it.

“Canada might want to request extra funding for hard hats, but there’s not much else that can be done about it,” said Chris Sands, an analyst at the Center for Strategic and International Studies, in Washington, D.C.

Though Bush announced in a speech Tuesday that he would move forward rapidly on the development of NMD, he provided little details about the technical aspects of the land-based portion of the shield.

That system employs 100 interceptor missiles based in Alaska that would most likely, analysts say, intercept incoming ballistic missiles before they have a chance to land on U.S. soil.

Those intercepts, however, would most likely occur over sparsely populated regions of western Canada or the Canadian north, Sands told the paper.

But there are no guarantees. The debris — depending on where the actual intercept occurred — could also land in heavily populated Canadian cities.

“Debris won’t fall on Toronto, we hope,” Sands said. “But who knows?”

Analysts say the quickest flight path for missiles aimed at the U.S., perhaps from North Korea, Iraq or even China, would be over Alaska and then Canadian soil.

“We are certainly under the trajectory, and our hope would be that (a missile) is intercepted before it comes near Canadian territory or after it has left our territory,” Brian McDonald, a Toronto-based military and defense analyst, told the Herald.

Analysts also said it was “doubtful” that Canadians would have much warning after an incoming missile had been successfully intercepted and came crashing down on Canadian soil. Depending on where the missile was launched, the weapon would take about 20 minutes to reach the United States.

But, U.S. analysts counter, in return for intercepting missiles over Canadian soil, the missile shield will also protect some Canadian cities from attack — theoretically.

Another Canadian Department of National Defense report acknowledged that, but also said that there may not be enough U.S. interceptors to prevent Canadian cities from being hit.

Modern ballistic missiles increasingly carry “decoys” that can be automatically released at some point during flight to fool U.S. interceptors. Therefore, many or all of the 100 interceptor missiles could be used on both decoys and real missiles, leaving some actual weapons free to come crashing down on U.S. and Canadian cities, the second defense report said, as quoted by the paper.

Canadian military sources say the U.S. is not expected to ask Canada to participate in the construction or maintenance of the shield, unless the Canadian government expresses an interest to participate — which it has not done.

Prime Minister Jean Chretien has said Canada has yet to examine all aspects of the U.S. NMD system and would need to do so before making a decision on whether to participate.

The Pentagon envisions a “multi-layered” missile defense shield, however, that would include the 100 land-based interceptors, as well as sea- and space-based interceptors. The space components would include laser weapons.

Using the multi-layer approach, Pentagon officials have said it is entirely feasible to be able to destroy ICBMs over an enemy’s nation, as the missiles just begin to gain altitude.

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