I don't agree with the hyperbolic Immanuel Wallerstein either, but his thesis at least has a virtue of clarity and attention to material conditions that Hardt & Negri's lacks, hence a better point of departure in debate on cycles of accumulation and stages of imperialism.
I do think that the 90s in the USA was only a short uptick in restoration of profitability achieved mainly by union-busting, cuts in social programs, increases in household debts, low prices of commodities that are staples of working-class consumption (except housing and health care), low prices of commodities that are main industrial inputs, and the like, (all of which are results of neoliberal class warfare from above at home and abroad), rather than a turning point toward a long cycle of accumulation based on epoch-making innovation and revolution in productivity. Capital can't restore profitability for long by simply squeezing the working class further, as they did with the neoliberal program.
What is noteworthy in today's imperialism is that, while capital has become global through the rise of productive forces in Western Europe and East Asia, the liberalization of financial regulations, etc., USA having lost its post-WW2 supremacy in production and capital export, political and military powers on the global stage are more concentrated in US hands than before. -- Yoshie
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