Up to half a million people joined last Friday’s climate change protest in Montreal, likely making it the largest ever demonstration in a city with a rich and tumultuous history of social protest.

The Montreal march was by far the biggest of the more than eighty rallies and demonstrations held across Canada on Friday, the last of eight days of coordinated “climate strike” protests around the world. However, large crowds, above all of young people, took to the streets in cities across Canada. An estimated 10,000 protested in Halifax, Nova Scotia, and an equal number in Winnipeg. More than 25,000 marched in Quebec City, and tens of thousands protested in both Ottawa and Toronto. Some 100,000 participated in Vancouver’s “climate strike” protest, and 30,000 more rallied in British Columbia’s capital, Victoria.

The scale of the protests attests to the growing recognition that climate change threatens ecological and social devastation, as well as to mounting popular anger at the manifest failure of the world’s corporate-controlled governments to seriously address this crisis.

That said, Friday’s protests were socially and politically very heterogeneous.

Indeed, much of the political and media establishment cynically lent them their support. This was epitomized by the participation of Prime Minster Justin Trudeau, flanked by fellow Liberal candidates for the October 21 federal election, in the Montreal march.

Anticipating student walkouts, Montreal’s main public-school boards and many CEGEPs (pre-university and technical colleges) cancelled classes for the day. On Sept. 25, Montreal Mayor Valérie Plante announced that public transit would be free across the Greater Montreal region on Friday as “a show of support” for the “climate strike.”

For tens of thousands of high school and college-age youth, Friday’s “climate strike” was their first-ever political protest. And under conditions of global capitalist breakdown—austerity and precarious employment, imperialist war and surging great-power conflict, and environmental crisis—and a global resurgence of working-class struggle, it will undoubtedly not be their last.

Delegations of teachers, nurses and other workers attended the Montreal march. But the vast majority came with classmates, friends or family.

Many brought hand-made signs. Some of these attacked big business and capitalism or focused on the imperiled environment. Others denounced consumerism and reputed excessive consumption—this in a world where the wealth of the 26 richest billionaires is equal to that of the poorest 50 percent.

“I am here because I am concerned about the risk the Earth will be destroyed,” Roger told the World Socialist Web Site. “What the governments are doing is insufficient. Financial interests pressure them to be ineffective. They are responsive to big business, to profit, and they focus on the short term, not the long term.”

Zoé, a special education teacher, said she was demonstrating because governments have failed to act. “From a global standpoint, I think we need pretty drastic action, but instead we have tiny steps. By mobilizing in great number, we will show that climate change must be addressed.”

In speaking with the WSWS, many demonstrators emphasized the global character of the protests and enthused over the size of the Montreal march. The politicians and corporate elite would have no choice but to listen, they added, and if they did not, the protests would only continue.

In reply, WSWS reporters noted that around the world the capitalist elite is lurching ever further right. Moreover, the global corporate struggle for profit and the economic and strategic rivalry among the capitalist nation-states constitute insuperable barriers to a coordinated global restructuring of the world’s economy from reliance on fossil fuels to renewable energy.

Trudeau met with a mixed reception at Friday’s march. Some gladly shook his hand. Others jeered him, for seeking to bulldozer through the expansion of the Trans Mountain Pipeline, to transport bitumen from the Alberta tar sands to Canada’s west coast.

Also joining the Montreal march were the Green Party’s Elizabeth May and Bloc Québécois (BQ) leader Yves-François Blanchet.

May and her Green Party have long served as close allies of the Liberals. Like the NDP, they have conspicuously failed to criticize the Trudeau government’s plans to hike military spending by more than 70 percent by 2026 and its integration of Canada ever more deeply into Washington’s military-strategic offensives around the world.

Only a few months ago, May was publicly signaling her readiness to prop up a Liberal government in the event that no party wins a majority on Oct. 21. Now, seeking to electorally profit from the growing concern about climate change, she is posturing that the Greens will refuse support to any government that is building pipelines and does not make its top priority meeting the UN target of a maximum 1.5 Celsius degree rise in temperature.

The BQ is the federal sister party of the Parti Quebecois, which has savagely attacked the working class whenever it has formed Quebec’s provincial government. At the center of its election campaign, the BQ has placed its support for Bill 21, a chauvinist Quebec law that targets religious minorities, above all devout Muslim women.

NDP leader Jagmeet Singh, for his part, joined the “climate strike” demonstration in Victoria. Unlike May, the head of Canada’s social democrats continues to publicly proclaim his readiness to prop up a big-business minority Liberal government.

If capitalist politicians like Trudeau, May, Blanchet and Singh could associate themselves with Friday’s “climate change strike,” it is because the perspective of its organizers did not go beyond a protest to the powers that be, to big business and its political representatives.

At the Montreal protest, supporters of the Socialist Equality Party distributed close to a thousand copies of a statement titled “The only solution to climate change is world socialism.”

The statement explained that climate change crisis could only be addressed by reorganizing socio-economic life so as to make meeting social needs, not private profit, the animating principle; and that the only social force capable of bringing about this revolutionary change is the international working class.

In opposing the perspective of “green capitalism,” it made a specific warning about the role of Québec Solidaire, an ostensibly “left,” pro-Quebec independence party that was among the principal organizers of Friday’s march.

The statement read in part: “We appeal to the students and others participating in the climate strike movement to not become ensnared in parliamentary politics and futile protests to the capitalist establishment.

“In this regard, a special warning should be made about the politics of Québec Solidaire. This pseudo-left party spent the past two weeks campaigning for Quebec’s rightwing, anti-immigrant premier, Francois Legault, and all the other big business CAQ, Liberal and PQ MNAs to join today’s climate change march. It is patently clear the fight against climate change requires global action and a challenge to capitalism. Yet Québec Solidaire presents it as a question that transcends class divisions and the class struggle, and—under conditions where it is clear the working class must unite its struggles across state borders and continents—seeks to revive reactionary Quebec nationalism by urging the fight against climate change be waged as a ‘national struggle.’

“The struggle against capitalist environmental destruction must be based on the working class, and it is to this force young people must turn. … The technology exists to solve the great social problems of our time: climate change, the destruction of jobs, mounting social inequality, the assault on democratic rights and the threat of world war. At the same time, scientific planning can ensure increased living standards and quality of life for the world’s population. But if technology is to be used rationally and in the interests of the world’s population, it must be liberated from the control of big business, their governments, and rival nation-states. The only social force that can achieve this goal is the international working class, through the method of world socialist revolution.”