The coalition, which calls itself Code Blue, wants UN Secretary Ban Ki-moon to lift the diplomatic immunity that protects UN employees from being held to account when abuse complaints arise.
The campaign has added relevance because of the scandal that erupted last month in Central African Republic with child sex abuse allegations against French soldiers involving boys, some as young as age nine.
Lewis said Ban's inaction makes a mockery of his annual pledge of zero tolerance towards abuse.
"Time and time again, on an annual basis, the secretary general reiterates the goal of zero tolerance, and time and time again, on an annual basis, the evidence that the secretary general himself presents makes a mockery of the phrase."
Lewis said sexual violence is more prevalent among the non-military international players — civil servants, police, experts and staff from UN agencies — but they are largely protected by a 1946 UN convention on immunity.
During a news conference Wednesday in New York, blocks from UN headquarters, he dared Ban to waive it more frequently.
"The ultimate decisions on the exercise of immunity in each and every instance rests in the hands of one man: the secretary general of the United Nations," said Lewis.
The one-time Ontario NDP leader served as Brian Mulroney's UN ambassador in the 1980s and campaigned with the Progressive Conservative prime minister to help end South Africa's racist apartheid regime. He has remained active in the UN and international affairs since then.
Paula Donovan, a campaign organizer, said she is hoping for the support of the Canadian government and its people because of the country's peacekeeping tradition.
"Governments like Canada have a very serious vested interest in peacekeeping and keeping it as noble as it was intended when you guys invented it."
With the backing of U.S. President Dwight Eisenhower, former external affairs minister Lester Pearson proposed the first UN peacekeeping mission in 1956 to help defuse the Suez Crisis.
Pearson received the Nobel Peace Prize in 1957, but in recent decades Canada's contribution to UN peacekeeping has dwindled. UN figures show that 22 Canadian troops are deployed on such missions, far behind the top three countries — Bangladesh at 9,300 and India and Pakistan at about 8,100 each.
Donovan said despite its low numbers, Canada continues to contribute technical expertise and money to UN peacekeeping, so it is engaged.
"The issue of sexual abuse and exploitation of children, those are all high on the Canadian agenda, so I can only hope and imagine that the Canadian government and certainly the people of Canada will embrace this campaign."
Nineteen years ago, Mozambique humanitarian advocate Graca Machel wrote the leading report on the issue, which documented a significant rise in child prostitution in six of 12 countries that had seen the deployment of UN peacekeepers.
"The evidence is that things have not changed, have not improved, apparently they have gotten even worse. You are all familiar with the recent events in Central African Republic," said Machel, who is also Nelson Mandela's widow.
Machel said all countries in the United Nations are responsible for the international peacekeeping missions that are deployed under its banner.
Therefore, she said, every country in the world is responsible for the shattered lives of women and young people that some UN peacekeepers are leaving in their wake.
"This is not about something which belongs to somebody else — it belongs to us," said Machel. "Just think about that, and take this as your cause."
Dallaire, who commanded the ill-fated UN peacekeeping mission to Rwanda during its 1994 genocide, said nothing can undermine the credibility or neutrality of a mission more than when the protectors of traumatized civilians become their abusers.
"There is no such thing in a conflict zone, or a post-conflict zone, as consenting adults," said Dallaire. "No fraternization, and no consenting adults means a barrier that cannot be crossed by those who are deployed."
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