The only thing you need to deter aggression from Russia is a large swarm of massive ICBMs aimed at every major city and economically important region.
The thing with Putin and Russia is that there´s a lot of things they can´t contain anymore due to social media, and young Russians are connected to American and Western online culture like never before. It´s going to sway voters away from Putin and his style of politics. If he manages to pull Trump or other future US president into an arms race of any kind that´s a huge win for him politically. His media puppets are of course going to control the narrative as it happens.