Equilibrium
Almost everyone agrees in an Arms race that it would be better if we didn't spend the excess resources, and in the case excess lives; in exchange for the security the arms provide. The problem is that we don't trust other parties to not take advantage of our weakness if we don't invest the resources and arm ourselves.
For example: the EU has achieved peace thought high rates of cooperation and trust. No one sees England invading France as a real problem, despite their long history of the blood shed. But Russia and France is different. If a relationship of trust and peace could be established, then both sides could start disarming without worry. But, many obstacles stand in the way, most notably Putins warmongering.
This leads to a fundamental conclusion about what it takes to deescalate: trust. Trust that your neighbors won't rob or murder you. Trust that your government won't oppress you. Trust that you won't be invaded.
Since trust is so hard, many opt for trying to be the biggest fish in the race, or at least tied for biggest. This strategy is called deterrence. But here we run into A real life Chekhov's gun. Two examples:
In the lead up to WW1 European countries pilled up arms "defensively", but inevitably the power cake exploded. Every one claimed to be doing in defensibly, and yet.Perhaps the most famous example is the nuclear arms race. Some will call this a win for deterrence, since so far its increased the cost of war so much that no two nuclear powers have yet risked it. But two issues: We don't know if wars would have happened without nuclear weapons and if they do (perhaps even a question of "when" and not "if" on a long enough time scale), the results will be so destructive that we seriously risk collapsing global agriculture or even ending all human life.
So, we want trust, but how. The question is very context dependent and changes a lot based of who/what the involved entities are.