also i skipped out on portable ops, peace walker, and ground zeroes. i'm trying to make sense of everyone's wants after mgs 3 leading up to mgs. please help out as i think i have most things wrong:
the boss wants to protect america and goes to extreme lengths to do this, including going down in history as a traitor and making her apprentice kill her. this sets in motion a shitload of stuff for the next 50 years.
big boss rejects the idea of ends justifying the means and tries saving the world through his own superhero spinoff group where he's in charge (again no 1970-1975 stories for me to understand this better). i assume that he uses the boss's death to find a better way.
zero on the other hand thinks the boss had some pretty good ideas, and uses the philosopher's legacy recovered during mgs 3 (it's been some time) to kickstart cipher. i believe he thinks he can keep the world safe on his own. skull face is a bad guy and really obviously a bad guy, but for some reason he's a person zero trusts a lot. skull face incapacitates zero and takes over cipher with the intent of creating a world he thinks the boss wanted, uniting it under a common enemy (which is what she became to the united states), which is also english (?)
to counter this, zero goes to extreme lengths to fight skull face and comes up with a plan to keep big boss safe by using a lookalike. by the time big boss wakes up in the 80s, it's been a long time and he actually flatlined after the helicopter crash, so he changes his tune and comes around on the 'ends justify the means' bit and goes along with zero's plan. big boss's plan is basically zero's plan from this point onward, believing he can save the world if he can control it. venom snake just wants a place free of nations. big boss twists it around a bit, which leads to outer heaven being a potential superpower and a threat to the world.
big boss sends in solid snake because this guy is a dumb rookie and will get captured in a way that benefits outer heaven. instead, solid snake really starts to fuck shit up. i'm not sure where kaz miller fits in during metal gear, but it seems this is when he turns against big boss? ocelot is nowhere to be found. solid snake kills venom snake, and big boss sets up camp in zanzibarland where big boss tries again but with feeling. big boss dies here a second time.
and then mgs happens and liquid snake wants to rule the world because he's superior (it's also been a long time since i've played mgs), but this is all a way for ocelot to get back at the patriots or something, a plan that he uses nine years later to bring the patriots down in mgs 4. at this point the ideals of the boss, big boss, and zero have all been lost to time and people are acting of their own interests.