For a very long time after I left communist Hungary I have been witnessing how numerous Western "Sovietologists" have been trying to clear the USSR of any responsibility for imperialism and, thus, the Cold War. In the April 2013 issue of Harper's magazine one James Leigh chimes in with a letter to the editor in which he raises the question of "whether Stalinist policies were prima facie evidence of a Soviet desire for world domination." He claims that the demonstrable brutality of Stalin's regime gives no evidence of a Soviet policy of expansionism. Rather, America's nuclear program is supposed to have been the "proximate cause" of the Soviet Union's imperialist attitudes and policies.
This is a position I have encountered even from stalwart libertarians, such as the late Murray N. Rothbard. He, too, if memory serves me right, blamed mainly the American government for pushing the USSR toward imperialism. In other words, the Soviet Union, however vicious, wasn't aiming to rule the world and the only thing that made it appear so is that America was provoking the Ruskies to be fiercely defensive.
I have always been curious how those who were blaming the Americans for being the aggressors in the Cold War managed to ignore a certain element of Marxian ideology and geopolitics. Given that Marx and his followers in the USSR were advocates and promoters of international communism (socialism), their intention to spread Soviet domination across the globe is difficult to deny and natural to fathom.
Marx himself argued, back in the 1880s, that the movement toward a communist future across the world had to involve spreading out the borders of socialist Russia. Marx explained: "If the Russian Revolution becomes the signal for a proletarian revolution in the West, so that both complement each other, the present Russian common ownership of land may serve as the starting-point for a communist development." [Karl Marx, Selected Writings (Oxford UP, 1977), ed., D. McLennan] Soviet expansionism, the "desire for world domination,' was consistent with this Marxist communist idea: The Soviet Union would be a "signal for a proletarian revolution in the West."
There are those Sovietologists and scholars of the Cold War who would ignore Marxian ideology as they propose to understand the behavior of the USSR. For them it was a mere epiphenomenon, not a guiding doctrine. Yet that ideology held that capitalism must necessarily be imperialistic so as to create foreign markets for capitalist nations. And the military of such nations were supposed to be bent on securing those markets coercively, so socialist countries such as the USSR needed to prepare for this. Ergo, the USSR must achieve global dominance lest capitalist nations do so.
It is true that capitalists want to reach foreign markets but by all accounts they would want to do this peacefully, through trade instead of military conquest. The idea that the USSR and not the USA was aiming for world dominance by military and political/diplomatic means is then a very plausible supposition. By all reasonable accounts that is just what transpired during the Cold War until the USSR fell.
Which doesn't mean that the Western governments were in no way responsible for a good deal of the malfeasance during the Cold War. But arguably the Soviets had an official state ideology that rationalized aggressive expansionism and imperialism far more readily than what guided diplomacy and military policy for the Western powers.