Its the closest you can come to class politics and leftism while still being liberal. MGS is still at its core pretty liberal though, as you can see about how the characters break apart on the whole "Boss' Will" thing and the solutions that they come up with, Big Boss being the only one that comes close to actually good for the world (MSF/DD being an army for 3rd world nations to fight off imperialism, like how they protected Nicaragua and Costa Rica from US meddling), while Zero basically opted for Cyber-dystopia and Skullface opted for mass-genocide to preserve language. And the real answer of the Boss' Will as per MGS4 is just let people decide their own fate for themselves which, alright, but the world is practically destroyed from the war economy, mass-refugee crisis have come out of the endless war, and the world is relapsing into it by Revengence. It's because the series still needs war to drive the plot but it is funny how the liberal solution of the entire plot just admits that it promotes what the Patriots did naturally, in reality the Patriots never needed to control the economy like they did to build up this coordinated war economy.