OTTAWA - The U.S. ambassador to Canada understands the frustration of cross-border travellers who've been ensnared in security restrictions since the 9-11 terrorist attacks.

David Jacobson has been red-flagged himself as a security risk.

"I have been stopped and (told), 'We're sorry Mr. Jacobson but we need more information, we can't get you on the plane,"' Jacobson told The Canadian Press in an interview.

"This happened once and they got it sorted out -- and then it happened again, not too much later."

Jacobson was ambassador at the time, a situation he acknowledged was "somewhat ironic."

Jacobson eventually discovered "there was another person with a very similar name" who had been deemed a security threat.

"I don't know what list they were on but they were not on the good guys' list."

He also discovered there was a relatively simple process for ensuring he wouldn't be delayed -- or stopped altogether -- from travelling between Canada and the United States in future. He contacted the American Department of Homeland Security, which has posted a redress procedure on its website, explained who he was and obtained a "redress number" to show to border and airport officials.

A spokesperson later said Jacobson's encounter with the U.S. no-fly list occurred in Canada but could give no further detail. Canadian airlines consult the U.S. list even for domestic flights.

Jacobson raised the incident during an interview about the 10th anniversary of the Sept. 11 terrorist attacks on the World Trade Center and Pentagon.

"This is a good example and there are lots of others, but it's a good example of this sort of myth that surrounds our process. We are not trying to be bad guys. We are trying to be safe but we are trying as best we can to be reasonable."

He allowed that reasonable was not always the watchword in the immediate aftermath of the horrific 9-11 attacks. And that some of the excesses may account for Canadians' continuing concerns about the prospect of a North American perimeter security deal.

Prime Minister Stephen Harper and U.S. President Barack Obama are currently working on the deal and Jacobson said they're still hoping to release an action plan "by the end of the summer."

According to reports released earlier this week by the federal government after an initial round of public consultations about the deal, Canadians are worried that Canada stands to lose some of its sovereignty and travellers could lose privacy protection of personal information that's shared between the two countries.

Jacobson said he wasn't "dismayed or concerned" about the results of the consultations. But he thinks an education campaign is needed to demonstrate that Americans' treasure their national sovereignty, personal privacy and civil liberties every bit as much as Canadians and would not agree to a deal that put those things in jeopardy.

"Not only are our values not all that different but our rules are not all that different," he said.

"There's also an urban legend in Canada that somehow or another, information that gets to the United States is just like fair game for anything and that bad information will be there forever and will haunt you to the end of your days. That's just not true."

It was true, however, for Maher Arar. The Ottawa communications engineer was detained in the U.S. in 2002 on suspicion of terrorism and, on the basis of inflammatory information passed on by the RCMP, was shipped to Syria, where he was imprisoned and tortured for almost a year.

A Canadian public inquiry subsequently cleared Arar and the federal government awarded him a settlement of $10.5 million. However, the U.S. government has refused to exonerate Arar and has publicly reiterated its belief that he's linked to terrorist organizations.

Jacobson would not comment on the Arar case, saying he's "not expert in the nuance of that." However, he suggested that the incident, which occurred under George W. Bush's presidency, would not have happened under Obama.

"I have a very high degree of confidence that the rules in the United States and the way they are enforced today are quite protective of individual rights and individual liberties.

"I'm not going to sit here and say bad things about other administrations but I know a lot about this administration and I know a lot about the values of the president and the values of the people who enforce these laws in the United States now. ..

"And I can assure you that they are as concerned about individual liberties and privacy (as Canadians)."

Jacobson said it's fair to say Canadians felt at times that the U.S. over-reacted to the terrorist threat, including the oft-repeated "goofy" assertion from some American politicians that the 9-11 terrorists entered the U.S. from Canada.

"One of the things that happened after Sept. 11, because it did impact on the psyche of the American public, was that all too often we were perceived as exporting fear."

But he said that's changing now.

"One of the things that I think we have come to grips with, for a variety of reasons -- part of it is the passage of time, part of it is the experience of doing it better, part of it is the political process -- but one of the things we've done is we've gotten much closer back to our historic role of exporting hope."

Jacobson acknowledged the Canada-U.S. border, once lauded as the world's longest undefended border, has become littered with barriers to trade and the free flow of travellers since 9-11. And he said the whole point of the perimeter security deal is to relieve some of that congestion, without compromising security.

"We in the United States ramped up security very, very quickly after Sept. 11 and it did not always go smoothly and probably no place was it more problematic than here because of the length of the border and history of what it used to look like and all of a sudden it was very different," he said.

"What we now believe, partly because we've had more experience, is that we don't have to choose between security on the one hand and efficiency and trade on the other, that if we're smart, if we work together, if we're creative, that we can have a North America that's more secure for everybody and we can have a border that is less of a barrier to the movement of safe goods and decent people."

Jacobson said he thinks criticism that the perimeter security negotiations have been secretive is "very unfair." He noted that there have been numerous public consultations on both sides of the border already and there will be more before anything is finalized.

"The reason we are doing all this consultation and outreach is because this thing is not going to be successful unless it has the support of the Canadian people and the support of the American people."

Jacobson unveiled Friday a photo exhibit of the impromptu memorials that sprang up outside the American embassy in Ottawa immediately after the 9-11 attacks.

"The reason we did it was to show our appreciation to the Canadian government, to the country and to the people for the generosity and the compassion and the outpouring of support 10 years ago at our darkest hour. That's something that we will not soon forget and that we are extraordinarily grateful for."