Sometimes it is argued that given the stranglehold of the world by the existing capitalist-imperialist powers, new capitalist-imperialist powers cannot possibly arise. However, the facts say otherwise.
The original leading capitalist-imperialist power was Britain. But during the latter part of the 19th century the new capitalist-imperialist powers of the United States, Germany, France and others all arose along with Britain, and despite its initial dominance. Early in the 20th century the new capitalist-imperialist power Japan arose, and Russia was also transformed from an old-style imperialist power into a fledgling capitalist-imperialist power (though with internal rather than external colonies).
Was that the end of the story? Of course not. Other imperialist powers have also developed over this period. And Italy, already an imperialist country by then, invaded Abyssinia (Ethiopia) in 1935/36 and turned it into a colony.
Then in the 1950s the once socialist Soviet Union, when it and the Communist Party of the Soviet Union were captured by a rising new state-bourgeoisie from within, also became a new capitalist-imperialist country. Mao appropriately called it a social-imperialist country, a country still hanging onto the “socialist” sign-board (until 1991), but in reality a new imperialist country.
This historical experience demonstrates very clearly that new imperialist powers can in fact arise in the modern era, even in the case of countries that were once actually socialist! It also demonstrates that a country which is partly state-capitalist (or even almost entirely so—as the Soviet Union was) can be an imperialist country just as much as one which is organized along the lines of private monopoly capitalism of the Western variety.
Although the social-imperialist Soviet Union was—alongside the U.S.—a superpower, it never “replaced” the U.S. as the world’s most dominant imperialist country. Rising new imperialist countries do not necessarily supplant existing imperialist powers.
In 1916 Lenin wrote that “Capitalism is growing with the greatest rapidity in the colonies and in overseas countries. Among the latter, new imperialist powers are emerging (e.g., Japan). The struggle among the world imperialisms is becoming more acute.”
In the early years of the 20th century too the dominant imperialist powers “had a stranglehold” on the world, and yet it was still possible for new imperialist countries to arise. It is a totally unsupported dogma that this “cannot” happen, and that it “cannot” have happened in the case of China more recently.
In some respects it is actually easier for a new imperialist power to arise in the post-World War II era in which capitalist-imperialism has become a world system. The export of capital, for example, can now begin without the necessity for a rising imperialist country to first conquer other lands militarily and then turn them into exclusive colonies, or else to first steal colonies from established imperialist powers through inter-imperialist warfare.
One of the objective reasons why the old colonial version of capitalist-imperialism had to be replaced by the newer neocolonial imperialist system was to set up the rules for all imperialist countries—including newly arising ones—to participate in the exploitation of the people of the world, and especially those in the more undeveloped countries. Moreover, the expanded horizon for the international liquidity of capital was a key motive for this new post-World War II imperialist architecture.
 Italy was already an imperialist country by World War I and joined the side of the British-French-Russian Entente in large part in order to expand its territory. In 1935/36 it conquered Ethiopia and in 1939 it annexed Albania which had been a de facto protectorate for decades.
 This is not the place for any extensive discussion of the social-imperialist Soviet Union, nor even to decide when, exactly, it could be said to have first become an imperialist country. It could be argued that the USSR became an imperialist country as soon as the new bourgeoisie seized control of the CPSU and government in the 1950s, since it already had political dominance over other Eastern European countries and immediately began exploiting them for the benefit of its own new ruling class. Or, as some argue, the Soviet Union only emerged as a full-fledged imperialist country around 1968 when it acted aggressively—invaded Czechoslovakia—and when Brezhnev promulgated his theory of “limited sovereignty” for the countries the Soviet social-imperialists had dominance over. The precise timing of this change is not that important; what is most important for us here is that this development of the Soviet Union as an imperialist power, and it along with its bloc as an imperialist system, did in fact happen.
 Lenin, “Imperialism, the Highest Stage of Capitalism: A Popular Outline”, (Peking: FLP, 1975 (1916)), p. 117.