This is possibly not quite the right place to ask this question but it's fundamental to the world I'm working on so here it is; if faced with a potent existential threat, in the form of an outside force, how will the human race respond?
The current scenario I'm working on looks a bit like this; humans are massively out numbered and hugely outgunned but in no way surrounded by, or even in frequent contact with, an alien race with which they can communicate but generally don't, because one sided conversations are boring. This alien race basically ignores the human race beyond securing their frontier from human intrusion, a thing humans can't begin to do in return. The frontier is static this race hasn't advanced in our direction since they became aware of us, but no-one knows if that's by chance or design, afraid of provoking a forceful response human colonisation in that direction has also ceased.
So the basic assumption I've been making is that if faced with a superior force that has shown it could destroy the human race, but doesn't, a de facto state of cold war would exist with humanity scrambling to build and spread to match their apparently unmatchable adversaries. I've made some accessory assumptions about large scale economic structure etc... based on this, and some setting shaping future history, but the underpinning of those assumptions is based in a response I'm beginning to wonder about; that being that the human race would, largely, stand its ground when faced by an alien race that is comprehensible (we understand them to communicate and more importantly the motives that appear to govern their actions), active (ambassadors "at court", open but generally quiet lines of communication), unfriendly (they don't talk much, won't trade and don't allow humans on their territory), non-belligerent (don't attack), but imminently and demonstrably capable of snuffing humanity out without breaking a sweat (they've vapourised everything that's ever crossed the border uninvited instantly).
Any examples from fiction or even better history would be most welcome here since the model I'm working from is essentially the Cold War, but that was a contest of more-or-less evenly matched opponents where this is as asymmetric as it gets.