If Bernie Sanders loses the Democratic Party nomination, does socialism also lose? A recent reading of Fidel Castro’s speeches from the late 1980s defending socialism cast a spotlight on the differences between building a real socialist society, in Cuba, and “socialism” as it is discussed in the context of Sanders’ election campaign.

Cuba’s revolutionary leader, in a 1988 book entitled “In Defense of Socialism,” provides key insights into what the defense of socialism looked like for Cuba in the last years of the Soviet period. Fidel explained to the Cuban people that “imperialism is trying to present socialism as failure in practice … and it is extolling to the utmost the alleged advantages of its selfish and repugnant capitalist system.”

This only intensified after the Soviet Union fell in 1991. The world capitalist crisis of the 1970s produced a general slowdown in production and prompted U.S. imperialism to escalate its war on socialism around the world. Many young people born after the Soviet period were left with little opportunity to examine the prospects of revolutionary socialism. These conditions supported Sanders’ rise in this year’s presidential elections.

A Nov. 5 CNN article suggests that the Sanders campaign is losing ground to Hillary Clinton. Clinton’s deep corporate support and long record of performance in service of the military industrial complex has ultimately made her the favorite for the Democratic Party nomination.

However, the number of months Sanders stayed competitive with Clinton had much to do with his self-proclaimed title as a “socialist.” He promoted policies such as student debt relief and universal health care to back up his title. But Sanders isn’t a socialist. Socialism must be defended from the misleading confines of the capitalist elections.

The appeal of Sanders-style socialism rests on the reality that workers and oppressed people are being drained by the crisis of U.S. capitalism. Savage austerity, ruthless privatization and heightened exploitation have degraded the social condition of all workers, especially Black workers. Simultaneously, U.S. capitalist society has continued to teach the masses that socialist countries such as Cuba are corrupt dictatorships at worst and unrealistic at best.

Sanders has been useful to the ruling capitalist class, even though they don’t reward him for this. His campaign hooked the growing number of disaffected workers back into the Democratic Party with his commentary on issues such as the lack of affordable health care and the predominance of low-wage work. He has done so under the assumption that such issues can be resolved under the dictates of U.S. capital.

The task at hand is to distinguish revolutionary socialism from Sanders’ politics so the two are never confused. The fundamental contradiction under capitalism is that between the tiny clique of capitalists that privately own the means of production and the billions of workers they exploit. The capitalists keep power through the army, police, courts and media that serve them. It is this social relationship that allows the bosses to exploit workers and oppressed peoples for immense profits here and around the globe.

Revolutionary socialism is socialized production administered by the government, popular army, and other forces that serve the proletariat and oppressed people. Until workers and oppressed people seize the means of production, i.e., the banks, factories and distribution centers by taking state power, no revolutionary country or movement is safe.

The seizure of state power by the oppressed masses is a necessary precondition to the fundamental transformation of the social relations inherent under capitalism. The state must be transformed into a body that no longer manages private property, but rather administers things. That is, the state must be transformed into an organ of the masses capable of suppressing the old order and implementing the necessary economic and political policies of the new. Sanders-style socialism keeps the old order intact and thus represents a variant of the ruling capitalist system.

This variant of the capitalist system fits snugly into the Democratic Party milieu. Sanders has openly endorsed the proxy war on Syria and the bloody invasion of Yemen currently being conducted by Saudi Arabia. He has a track record that includes support of the U.S. invasion of Afghanistan in 2001 and a staunch defense of Israeli expansion in Palestine.

Sanders’ support of imperialist war is a negation of socialism. Imperialist war only serves the interests of the ruling capitalist class, which requires endless warfare in order to expand into new markets and maintain influence in old ones.

This is not the type of socialism Fidel was defending when he addressed the Cuban people at close of the 1980s. The Cuban people were defending revolutionary socialism, a social system that has been in place in Cuba since 1959. Under revolutionary socialism, Cuban workers hold ownership over the means of production and plan the economy around the necessities of housing, health care, and education for all. Cuban socialism has fulfilled these necessities for the vast majority of Cuban people.

Cuban socialism is rooted in international solidarity, not imperialist war. Hundreds of thousands of Cubans fought alongside anti-apartheid forces in South Africa and continue to stand with the peoples of the world through the administration of free, quality health care. Cuban socialism is a model for the oppressed.

Even if the Sanders campaign raises domestic issues that a workers’ party would support, his style of socialism is a model for the oppressor. There should be no question that it is Cuba’s socialism we defend.