Arguably any set of affairs imposed on a populace by an external force are imperialism, since even if they aim to create an equal relation between the two it will be from the perspective of the victorious power, who will be ignorant of particulars to the local area and its customs.
The MacCarthur rule of Japan is perhaps the best example of foreign occupation not being imperialistic in nature, and that's only if you ignore the defense aspect. Which could theoretically be improved upon utilizing the same model. Though then again, it was Japan which insisted they no longer have an army, provided the US defend them.
MacCarthur did so by being a dictatorial guiding hand akin to a somewhat more powerful and benevolent constiutional monarch, seeking out local japanese to build up their country and only removing or vetoing those who were fascistic as fuck or commies.
Commies moving in even in the best case scenario might be like "We come to liberate, comrades, where is the car manufacturers union? We wish to converse with them." and not paying heed to the fact that while THEIR country chiefly produces cars, the occupied one is a fridge maker, and giving more time to the car manufacturers and such.