but their economic model does not require it

i think you're defending this from the wrong angle, their economic model absolutely requires imperialism to be sustained

but that's the case for every capitalist country in the north, with or without welfare - their whole supply network relies on a price system that sits upon the exploitation of workers and the plunder of resources from the third world, both of which can only be maintained through imperialism

so the better angle is probably to just say it makes no difference, the country already relies on exploiting the third world, this is just about shifting the distribution of the spoils