Assuming that the left gets its shit together before Homo sapiens goes extinct.
My vote goes to either the USA or France. Especially because the Paris Commune already happened. “Smeagol did it once...he can do it again!” Paris seems to have been packed with rioters 24/7 for several years. Not so different maybe from the American Midwest. The ruling class is investing heavily in police in both countries. It’s afraid!
I know this seems partly delusional of me and that there is far more hope in the Global South unifying and then strangling the imperial core from the outside. But still, gun to your head, pick an imperial core country and explain how and why it will fall first. Marx, after all, predicted that socialism would come first to those places that had progressed along capitalist development the most. (Yes, you are invited to explain how wrong I am about this.) The USA falling to socialism would probably cause the rest of the planet to fall the same way.
edit: my choices seem embarrassing now, thank you for enlightening me comrades.
Gotta say I don't really understand that map at all. It seems to just measure "blue is the good countries, red is the bad countries". Like why is mexico on here but not like, idk turkey or something. It doesn't seem to give any real metric to qualify a country to be core or periphery.
Also, on the topic of comparisons, Ireland is like... not a rich country. There are a lot of rich people here who tip the scales on the GDP numbers, but in real terms, the working class of Ireland aren't amazingly wealthy. Most people spend a huge amount of their income on insurance and rent. The country experienced a boom in the 90s, and was one of the hardest hit countries in 2008. The Irish economy is reliant on foreign companies. So I don't see how it's a core country.