Beefed-up Coast Guard patrols, complete with armed police officers, have commenced along the St. Lawrence Seaway and the Great Lakes.

While the patrols will still deal with old problems like cigarette smugglers and illegal immigrants, the top priority now to deter terrorist threats to bridges, ships and nuclear power plants.

"It's not a question of if we'll ever be attacked, it's a question of when we'll be attacked, and diligence tells us we must be prepared on every front," said RCMP Chief Insp. Mike McDonell.

"We are definitely in a position to respond more quickly and adequately to any threats," said RCMP officer Jean Lemieux.

The new patrols are part of a federal government pledge in the last budget to spend $300 million over five years to fill holes in maritime security.

But critics say there are only three ships to cover the entire seaway and the four Canadian great lakes.

"It's not dealing with the problem, even remotely," said Sen. Colin Kenny, a Liberal who chairs the Senate's defence committee.

He calls for a much bigger armed fleet and dismisses the patrols as a public relations exercise.

"I think this is a dog and pony shows designed to impress the folks," was how Kenny summed it up.

Peter MacKay, deputy leader of the federal Conservative Party, said: "This is really just a drop in the bucket. They're basically taking resources from one area and moving them to another."

However, officays say 40 other Coast Guard vessels could be pressed into service if necessary, and say better intelligence will help the three armed ships hone in on any problems.

"What we do not want to do is just go out and randomly patrol and, if I may use the term, play 'go fish' -- we want to direct our resources to the threat," McDonell said.

Four new ships are being built, but they won't be ready until 2009