The July 2016 paper was prepared by the strategic joint staff, which provides analysis and advice directly to the chief of defence staff, and was obtained by The Canadian Press through the Access to Information Act.

The paper also warns about the need to clearly explain why whatever mission the government chooses is in the national interest and expresses real concerns about the threat posed by terrorism.

That is one of the main messages of an internal paper that military officials prepared last summer as they considered the challenges associated with the Liberal governments' promised return to international peacekeeping.

OTTAWA — Make sure you have a plan to get out before you actually get in.

A Canadian military instructor looks on during Ukrainian military exercises at the International Peacekeeping and Security Center in Yavoriv, near Lviv, on July 12, 2016. (Photo: Yuriy Dyachyshyn/AFP/Getty Images)

It emerges as the Liberal government continues to dither over where to send up to 600 Canadian peacekeepers, despite pressure from some allies as well as the UN for a decision.

The Liberals had been leaning toward — but have since waffled over — sending troops to the African nation of Mali, where more than 100 peacekeepers have been killed, many in terrorist attacks.

The government won't say when it will choose a mission, or why it is dragging its feet, but the issues and concerns raised in the paper may explain part of the delay.

One is the need to start thinking about an exit strategy even before the first troops arrive.

The paper notes that while countries like Canada often want to make only short-term contributions to UN missions, history has shown that there is often "significant pressure" to stay longer than expected. Canadian soldiers joined a UN peacekeeping force in Cyprus in 1964 and stayed until 1993.

"From the outset of planning, consideration should be given to the sustainment and eventual withdrawal from the (operation)," the paper reads, adding that leaving is often "a delicate mission to execute."

The government was encouraged to essentially line up other countries to step into the breach once Canada's commitment expires — a task that could be easier said than done for a mission like Mali.

Part of the reason Canada has faced international pressure to go into Mali is because some of the European countries already there have had trouble finding replacements.

The paper also says that moral arguments about peacekeeping being the right thing to do aren't a good enough reason for deploying troops on specific missions.

"There is a legitimate moral component to this discussion, namely that Canadian participation is the right thing for a nation with Canada's good fortune, wealth and means to undertake," the paper says.

Peacekeeping expansion serves national interest: Liberals

"But the discussion must be wider than a moral one in order to define the national interest in more tangible terms and to provide some balance by measuring the risks and rewards."

The Liberals have said expanding Canada's participation in peacekeeping serves the national interest by contributing to a more peaceful and stable world.

But government sources have admitted they must do a better job explaining why the Liberals are intent on peacekeeping — a task that will become even more important once a mission is chosen.

Much of the paper focuses on the new dangers that have crept into peacekeeping, with officials noting that missions "are higher-risk and take place in more complex environments than before."

Special attention is paid to terrorist organizations, which the paper says "pose an undeniable threat in certain locations," especially when it comes to protecting troops and fulfilling a mission's objectives.

Effect on Canada's reputation also a factor

This is especially true for UN missions, the paper says, which aren't mandated to conduct counter-terrorism operations.

While Mali isn't mentioned, the findings are particularly relevant to the mission there, as groups such as terrorist groups such as al Qaida in the Islamic Maghreb have repeatedly targeted peacekeepers.

Other factors to consider before choosing a mission, the paper says, are whether it is effective or could be made effective and what impact it could have on Canada's international reputation and national security.

"Canadian participation . . . should be grounded in a well-conceived and articulated strategic purpose, delivered via a strategy nested with other Canadian efforts globally," the paper concludes.

"It must reflect the contemporary operating environment, is mandated to have protection of civilians at its heart and should seek to promote responsible burden-sharing within the international community."

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