The only possible conclusions are
a) the USSR was not a socialist state, or
b) the USSR did not engage in imperialism
I bet I know which one you'll claim is true.
The one that conforms to reality (which is b).
Imperialism is a distinctly capitalist relationship, but even
hegemonic powers in the pre-capitalist era that called themselves empires reduced and local rivals to conditions of subservience benefited materially from the vassal states.
In contrast, the living standards and level of technology in the supposed "vassal states" of Eastern Europe was typically
higher than in the Soviet Union, and Soviet trade balances with other countries like Cuba and Vietnam were extremely negative for them, costing the Soviet Union a great deal of money. It would be a strange empire indeed that invested and built up its empire to a level of socioeconomic development
superior to its own. Indeed, it would match no definition of imperialism known to exist.
The only way you can even pretend the USSR was an empire is to deny reality. And even then you are only at best equating it with the criminal regimes of the West, whose empires pillaged the world over to build supposedly "great civilizations" in Europe.
But weren't you, as recently as a few pages ago in this thread, telling us that in all types of societies wealth comes from labor? So what is the 'huge difference'?
Yes exactly.
Whose labor? Is it the labor of the people benefiting from the products, or is it someone else? Capitalist empires exploit Third World labor for the benefit of the First World. They constitute a net drain of wealth from the Third World to the First. That is not "sharing our wealth" that is sharing booty. In contrast, the wealth enjoyed by socialist societies is wealth from the people who are benefiting from it. They all created the wealth, and they all share in it, the products of their own labor.
That's the difference. The British welfare state just spread around the benefits of a capitalist
empire more evenly
in the homeland. Socialism, in the USSR or China or wherever, spreads around the wealth
among the people who created that wealth.
If a capitalist welfare state were
really the same thing, they would be returning the wealth their empires stole back to their former colonies. You would see a vast, vast investment from Britain into Zimbabwe, and Egypt, and India, and Jamaica, and everywhere else, to bring them up to the same level of social wealth as Britain enjoys.
In other words, the relationship between the USSR, China, and other socialist states, whose nature I described above.