The Japanese Empire needs a powerful bloc to secure its position of power in the Pacific and Asia. So why not look back on the East Asian Co-Prosperity Sphere of WW2 and restore it? Modernizing it to work in the Present Day and to better connect the powerful states of East Asia! To start out, we begin inviting states like Thailand and the Philippines, nations that Japan may have claimed in the past like in the Philippines case, but it is more valuable in this moment to try and align them with an alliance before seeking to annex any of them. If they accept our alliance, (Thailand wouldn't be annexed either way btw), then any sort of Unification will be a peaceful ordeal or so we hope. However, we simply want strong economic and military allies to counter that of the Russians or the Australians.
This is NOT a response to Vladivostok's roleplay