Russian kit
One of the things missing from the multiple articles written about this is that this is Russia regaining the capability to build ICBM's.
The USSR's missiles (which are aging and need replacing) were made by Ukrainian based design centers.
Funnily enough, those Ukrainians don't feel much like rearming Russia.
So they had to build from scratch. Whats the point of building last generation weapons when you are starting again?
Its actually quite remarkable how far they've managed to come.
Before anyone questions whether Russia should be spending this money like this, two things:
1) Their defence projects cost one tenth of US ones - vastly more effecient.
2) Whilst there is poverty in Russia, its actually percentage wise on par with the USA and numerically less than half of US poverty figures.
Russia also has vivid memories of the Great Patriotic War. Sure we all lost people in WW2, but nothing like they did. They absolutely will not stand for it to happen again. Trump makes noises about US rearmament, tearing up the ABM treaty and the first use of nuclear weapons, Putin MUST respond.
Additionally China is another direct threat to Russia (and have attacked them before) and nothing short of nuclear weapons will keep them at bay across a vast land border.
Whether of course any of their new kit will actually work is another matter... I'd guess some will, some won't.
This course of action by Putin was entirely predictable with all of the PR stunt being about him being re-elected (of course pretending all the while that its actually a fair election and that he needs to actually persuade voters to vote for him.... which he doesn't really)