Nuclear deterrence is a top priority for Russia (for obvious reasons
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) . Now , they have a family of very good liquid-fueled missiles from Sineva/Layner family , with decent capability to defeat ABM defenses . Only problem is that they are liquid-fueled , and therefore more expensive and difficult to maintain .
On the other hand Bulava is solid-fueled (cheaper to maintain) but it had to retain liquid fuel in third stage for terminal maneuvering (it is much easier to change amount of thrust rocket engine produces with liquid fuel then with solid ) . This kind of hybrid concept is difficult to achieve , especially in the state Russian industry is today . We will yet have to see what would happen with this whole project .
that is also true, nuclear deterrence well where do you start, a SSBN is not a military weapon its a political weapon, but then it is a military weapon of huge significance
SSBN is basically a eqaulizer, a balance and a very good one at that, if you build SSBN the minimum number is 4, one in re-fit, one in dry dock, one on excercise and one on active patrol, theres no two ways about it four is the magic number
do i believe in deterrence, 100% yes, do you need SSBN? eh i think 90% yes because theres no way to guarantee a strike without a submarine, air force cant do it and ICBM cant do it
for any top tier navy SSBN is must, is Russia today a top tier navy? but then Russia has always been big on nuclear submarines
on the balance of probabilitys i would say SSBN for Russia right now is over-reaction, for top tier navy have carrier battle groups of which Russia has one but hardly of any signifcance
a single Typhoon SSBN was as expensive as a CVG, what is fate of all of them, all gone within 30 years much of that time spent in port