One has to ask why they're telling the world about it. There is apparently more value in letting the world know than keeping it a secret.
There are two contenders for why that might be: 1) A deterrent against other countries (probably the US, but maybe China) where they otherwise feel vulnerable, or 2) they're looking to sell it to raise cash.
HF
it's the dr. Strangelove theory
it ain't a deterrent if others don't know about it!
perhaps they finally managed to build that doomsday machine?
If Putin is to believed, then "...which other nuclear powers do not and will not possess." would seem to indicate they don't plan to sell it...
"One has to ask why they're telling the world about it. There is apparently more value in letting the world know than keeping it a secret."
More likely he's doing it for domestic reasons. Patriotic Russians like to have something to cheer about from time to time. Seems strange that they would waste the money on something like that, but hey, politicians are specialists at wasting money.
Perhaps they should have waited for the Premier's birthday - you know he likes surprises! ;^D