The trouble is Putin is a megalomaniac and egotist and I wouldn't put it past him to eye up the big red button if things go bad for him,I'm presuming that it's not as easy as pressing a big red button and there's a series of procedures to go through before setting off the nukes?
Would the Russians who are immediately in power behind Putin let him do it knowing that it would be the end of Moscow and other cities,if there is any nukes heading our way then I'm fine with them heading straight towards my house rather than sitting in a post apoptotic Nottingham