By Evan Dyer · CBC News

The leaders have a to-do list, but tensions over Trump's policies threaten to sweep it off the table.

There is an official agenda for this week's Group of Seven summit in Charlevoix, Que. — though it may be a struggle to get the leaders to stick to it. 

There are going to be so many sources of pent-up tension between U.S. President Donald Trump and the other leaders in the room, and so little time to air them. Trump will be on the ground in Canada for only 28 hours.

Governments hosting Group of Seven summits typically select themes that are as non-controversial as possible, and then couch them in vanilla language that everyone can get behind. Canada in 2018 is no exception — the Charlevoix agenda runs to five key themes:

• Investing in growth that works for everyone;

• Preparing for the jobs of the future;

• Advancing gender equality and women's empowerment;

• Working together on climate change, oceans and clean energy; and

• Building a more peaceful and secure world.

But even the innocuous themes chosen by Canada threaten to expose deep rifts between the Trump administration and U.S. allies.

How do you discuss "jobs of the future" with a president who wants to recruit the next generation of coal miners? How do you agree on "growth that works for everyone" with a president who sees trade as a zero-sum game in which, for America to win, everyone else has to lose?

Getting on the same page

In the joint written communique documents G7 summits typically end with, the leaders focus on those issues on which they can agree.

At last year's summit in Taormina, Italy, they were able to produce a statement of common goals on a number of foreign policy issues, including Syria, Libya, ISIS and North Korea. They endorsed "the importance of the rules-based international trading system." A vague statement in support of gender equality also made the list.

But on climate change, the leaders could not produce a consensus statement that Trump would sign. Just three days after returning to Washington from Sicily, he would pull the U.S. out of the Paris climate agreement.

Those differences on climate remain as stark as ever.

And climate is not the only environmental issue on the Charlevoix agenda.

Marine debris and plastic pollution are shown along the coastline of Haiti in a handout photo. (Timothy Townsend/The Canadian Press)

Oceans of plastic

The Trudeau government has taken several steps to protect Canada's oceans and coastlines, including the creation of new marine protected areas.

But for reasons that are not clear, the Trudeau government chose to make plastics in the ocean a signature issue of its G7 presidency, without planning any concrete actions that might show leadership on the issue.

Meanwhile, other governments have forged ahead with actions of their own. When Trudeau visited the Commonwealth Summit in London in April, he was upstaged by the British government's announcement of a ban on certain single-use plastics like straws and coffee stirrers.

Four days later, Canada's minister of environment opened a consultation on the topic. "Share your ideas about how Canada can reduce plastic waste and marine litter," says the official document. "It's time to take action."

Meanwhile, the European Commission last week unveiled a proposal to ban most single-use plastics and put the clean-up burden on manufacturers.

This week, NDP MP Gord Johns — who is pushing a motion on marine plastics that would require Canada to take some of the same steps its European counterparts are taking — joined with the grassroots campaign group SumOfUs to present a petition with over 100,000 signatures asking the federal government to move from talk to action.

"We need the government to take leadership," said Amelia Meister of SumOfUs Canada. "This is very low-hanging fruit.

"There are communities and countries all over the world that have taken leadership on this and shown that plastic bag bans and straw bans, and so on, can be implemented, and there's no reason why it can't happen in Canada."

Ivanka Trump, daughter of U.S. President Trump, participates in a roundtable discussion with female executives and Prime Minister Justin Trudeau at the White House, in Washington, D.C., on Monday, Feb. 13, 2017. (Sean Kilpatrick/Canadian Press)

Gender equality

Donald Trump may be a bête noire of the feminist movement, but gender equality is one of the official G7 themes on which the leaders might be able to agree.

Perhaps out of a desire to bury his infamous comments about groping women, Trump has shown himself to be amenable to initiatives that empower women — such as the Canada-United States Council for the Advancement of Women Entrepreneurs and Business Leaders he created jointly with the Trudeau government in February 2017.

This is one area where Canada may have something concrete to announce, perhaps in the form of a pledge.

"I think it's fairly certain that the G7 countries have some kind of agreement around gender equality," said Meredith Lilly of the Norman Paterson School of International Affairs. "Something to do with women's leadership or girls' education, particularly in developing countries, because you wouldn't see the kind of public announcements we're seeing now if they didn't already have that in the bag."

U.S. President Donald Trump and Russian President Vladimir Putin at the Asia-Pacific Economic Cooperation summit in Vietnam in November 2017. (Mikhail Klimentyev /AFP/Getty Images)

'A more secure and peaceful world'

This catch-all theme of Canada's G7 presidency likely will involve discussion of several topics that came up last year in Sicily, with North Korea's nukes moving up the priority list and the moribund Islamic State slipping down.

But new tensions have emerged recently among the G7 countries on issues of global security, following unilateral U.S. decisions to abrogate the Iran nuclear deal and to relocate its embassy to Jerusalem.

Russia remains a wild card. Last year the G7 talks about Russia focused on Ukraine, but there is a desire among some G7 members to discuss cyber threats and election meddling by the Kremlin this year. Russian attempts to interfere in the French and German elections, as well as emerging evidence of its involvement in the Brexit referendum, have concentrated European minds on the topic.

But to the U.S. president, any mention of Russian election interference is "fake news" and an attack on his legitimacy.

In the interests of presenting a united front to the world, the leaders may choose to focus on issues where the western alliance is least fractured: Russia's actions in Ukraine and its annexation of Crimea, North Korea's nuclear program, and the fight against Islamic extremism.

"There will be ongoing agreement around the South China Sea, which is a topic of particular importance to Japan," says Lilly.

United States Treasury Secretary Steven Mnuchin. (Jonathan Hayward/The Canadian Press)

Trading barbs

Trade fits under the heading, 'Growth that works for everyone'. That pillar of Canada's G7 presidency was supposed to be the topic of the G7 finance ministers' conclave in Whistler, B.C. last week.

But President Trump's steel and aluminum tariffs, it turned out, didn't work for everyone. They led to a testy exchange which saw six finance ministers ganging up on U.S. Treasury Secretary Steven Mnuchin.

A reportedly chastened Mnuchin returned to Washington, where some U.S. media outlets said he tried to persuade the president to roll back his tariffs, or at least to exempt Canada. (The White House has denied those reports.)

Now the U.K., France and Germany, annoyed by Trump's decision to renege on the Iran deal, are making clear they will also press the United States to guarantee them immunity from secondary sanctions for trading with the Islamic Republic.

Last year, all seven leaders were able to sign off on a statement affirming "our commitment to keep our markets open and to fight protectionism."

It's hard to see that happening this year.