Headcanon : Snake and Fox
4am tl;dr on Snake and Fox does this make any sense. Mostly tentative and perpetually under construction because what do I know about anything. 8|a My knowledge of the earlier MG games is kinda spotty at times, too. |Dc /worst Snake mun ever.
I admit here and now that I'm probably not hugely qualified to make sense of it from Fox's end. (Or Snake's for that matter.) BUT. As Niki and I have discussed: Big Boss was gone, possibly dead. Now here's a guy that looks JUST LIKE BB, if younger, who BB has trained himself, and who just defeated BB in combat. As we've covered before, it's entirely possible, even probable, that their relationship was not really all that healthy on Fox's end, at least in the beginning. (what are healthy relationships in Metal Gear anyway.)
But I like to think the friendship was truly mutual, eventually. If only because Snake needs SOME actual positive relationships in his life, even if they're still a bit dysfunctional. (Hell, Fox does, too.)
As for Snake, yes, he's pretty lousy with people. Unlike Big Boss, he's not a charismatic leader or anything. It's implied that the clones are legitimately less “human” than BB in a lot of ways. He's slow to get close and to trust, which gets worse with each betrayal, and ends up completely pushing people away by the end of it all, until Shadow Moses (and actually starts to do it again in MGS4.) But he kinda needs them, too. MGS1, for example, is the game where he manages to finally learn to be a bit more of a person, instead of just a soldier. He'd gone all reclusive and shut himself up for years, and even though he did his very best not to let anyone in, he ends up with a girlfriend and a future BFF out of the deal. The only people he counts as friends before that are Campbell and Fox, even years after Fox's supposed death. So he really does consider Fox a close friend, right up to and past facing him on the other side of the battlefield and beating him to death in a climatic barehanded minefield fistfight. YUP.
He first met Fox properly at Outer Heaven. Of course, he would have known OF him before that, since Fox was not only a part of FOXHOUND and an experienced agent, but BB's right-hand man. I can't say which one of them really initiated actual sustained contact afterward, though I'm sort of leaning toward Fox, just because I can't see Snake reaching out to anyone very easily, and the aforementioned “Fox is messed up” reasoning. Though it's possible they just spent a lot of time in the same general area during the massive debreifings that likely happened after OH and all and gradually started seeing more of each other that way.
Either way. Snake wasn't really a rookie, by far - he was a Green Beret during the Gulf War, and you don't get into FOXHOUND unless you're already a BAMF anyway - so its not like it was his first time on the battlefield. It was, however, pretty damn traumatic. Take into account that Snake was not only used and betrayed by a man that he had been loyal to as a commander and admired as a soldier, but forced to gun him down as well. During his first solo mission to boot, which he was never actually intended to survive. As for FOXHOUND, there was probably a general level of camaraderie there, but I don't see Snake as ever having known how to be too social, even when he was younger. With Snake being the reserved kinda guy he is, and without anyone he was particularly close to, and with the whole unit dealing with the fact that their commander had turned on them...I doubt he'd find himself able to share much of what he was feeling over OH with anyone else. (Couldn't have been easy to be known around base as “the guy who shot Big Boss.”) Which means he was left struggling with it on his own. He canonically has problems with this. PTSD, nightmares, etc.
Fox had been there at Outer Heaven - was the only other person that had. Snake would have had trouble understanding what had happened, and why. I'm sure the temptation was there, to ask just how much Fox had known about it, as close to BB as he'd been. But I don't think he ever would. He's canonically said that he and Fox had an unwritten rule in which they never really discussed their personal lives. (Such as they were.) Snake didn't know about Fox's past, his name, or about Naomi until he was told these things later on. And although Fox's involvement in OH wouldn't necessarily count as “personal life,” since it was a military operation, it was pretty personal. For both of them.
Snake says that he was “still green” and that Fox “showed him the ropes,” and that he “learned a lot from him.” Little of this happened onscreen in MG1, so I assume that it happened sometime between then and when Fox (and then Snake) left the unit afterward. Snake received training from Big Boss personally before Outer Heaven took place. With BB gone and them spending more time together, it's possible that Fox took his place, in that way. Less as a teacher-student relationship and more as equals. (In MG2 Fox calls them the “two greatest rivals in FOXHOUND.”) Especially since both of them enjoy a good fight, they probably did so on a regular basis.
As for how they actually interacted...IDK. Fox was a crazy-ass awesome ninja and everyone in FOXHOUND looked up to him. Snake included. I don't think he'd ever go all openly fangirl like Meryl or Raiden, but he had a great deal of respect for him as a soldier, even before they met. Seeing him look so cool under pressure at OH would have only increased that. Instead of following in BB's footsteps, Snake later teaches Raiden at the Big Shell in much the same way that he learned from Fox.
Fox is also like. One of very few people in Metal Gear who can be more stoic than Snake. I imagine their friendship involved a lot of companionable silence. A lot of unspoken understanding and quite a few unspoken rules (like “we do not talk about our personal lives”), and a loooot of periodic beating the crap out of each other because violence is cathartic. It would have been a VERY different kind of relationship compared to his other best friend in the series. And, I think, one that he missed a lot when Fox was gone, because there are some things that Otacon just can't ever “get;” not that Snake particularly wants him to.
And then they try to kill each other. 8|a But for all the dick-move trying-to-kill-him Fox did in Zanzibar Land, he also helped Snake out a WHOLE LOT in secret. Fox calls it “payback” to make up for “being so selfish.” Snake later claimed it was “just two soldiers doing their jobs,” “like a sport” and that “war is no reason to end a friendship.” But I think that it's because of all that help, and the fact that he can't bring himself to fault Fox's reasons for his loyalty to Big Boss, that Snake can't view it as a betrayal as he did with BB. When they're (sorta) on the same side at Shadow Moses, even though it's what Fox wants, Snake can't bring himself to kill Fox a second time.
When Fox comes back in MGS as the cyborg ninja, the only way he can find peace is through another fight to the death with Snake. Because Fox does seem to hold Snake up to a pretty high regard as well. Instead, Fox regains himself long enough to sacrifice himself to save Snake and take out REX's weak spot. Snake doesn't actually pass on Fox's last words to Naomi, because he understands to some degree the power of legacy. He understands why Naomi did what she did and forgives her for it, and passes on the sentiment, if not the words, so she can remember her brother fondly. Fox's dying words to HIM, on the other hand, became a driving force in Snake's motivations for the rest of his life.