If we do not have enough deterrence to maintain territorial integrity (as of now) against Russian military aggression (by virtue of the cost model being broken)

If we do not have enough deterrence to maintain territorial integrity (as of now) against Russian military aggression (by virtue of the cost model being broken), then what is going to deter Russia from dragging us into a localized conflict tomorrow if we announce we are joining NATO day-after-tomorrow? I mean, something has to guarantee that we have no conflicts between now and being an actual member AFAICT. There's talk of "safety guarantees IF we start membership procession" or something, but then there's still a gap where we need to guarantee territorial integrity / "no conflict". The point being, if we can deter them from attacking us between now and being a member (when attacking us would have higher ROI for Russia, stopping our NATO track) ... we have the deterrence to stop them from attacking us without NATO membership too (since it would be costlier for them in that case relatively speaking, the ROI would be lower).