Director, Nuclear Information Project, Federation of American Scientists. Tracking nuclear arsenals, writing Nuclear Notebook, SIPRI Yearbook. Opinions my own.
Putin has previously used nuclear rhetoric against West during his war in Ukraine but this is to my knowledge the first time he has ordered tac nuke exercise of forces in district off Ukraine with explicit reference to West. Obviously intended as a signal.
The link has changed. Here is the new one: bloomberg.com/news/articles/…
2/n We were taken into the P-tunnel where they’re conducting nuclear test verification experiments, 950 feet down into the PULSE (U1a) complex where the labs do subcritical plutonium implosion experiments for nuclear weapons (I saw LLNL’s upcoming NIMBLE device).
2/n - This includes “strengthen training and exercises that simulate” conv & nuc dimension of a crisis/conflict to get “greater coherence between conventional and nuclear components of NATO’s deterrence and defence posture across all domains and the entire spectrum of conflict.” 
Much uncertainty and confusion from initial reports about what he actually said. More nuances here: 
B-52 (60-0026, HOJO11) is continuing far west. Possibly one of a pair. @SirListenalot reported possible return to Minot AFB. Bomber Task Force to Moron AFB began a month ago with overflight of Tallinn and has involved noteworthy operations over Baltic region. 
Mission over norther Norway complete, B-52 (60-0026, NOBLE61) heading south after overfly of Tromsø. 
I have questions…about US sub building capacity, sale of sensitive technology. Hopefully more clarity after San Diego meeting later today.
Interesting that EUCOM announced B-52 deployment as the bombers were on their way. Normally they announce it after.
2/n - The first is that each silo in 3 new new missile silo fields "can be equipped with the CSS-10 Mod 2 ICBM [DF-31A], which is capable of ranging the continental United States...with...MIRVs."
2/n - On reason for China's nuke buildup: Beijing has "concluded that their current capabilities are insufficient [and] worries that bilateral tension, US nuclear modernization, and the PLA’s advancing conventional capabilities have increased the likelihood of a US first strike."
After Denmark, the two B-52 bombers are heading east over the Baltic Sea and turning southeast over Poland for a display of force and training in the region. The two aircraft 60-0026 (NOBLE12) and 60-0056 (NOBLE11) are both nuclear-capable, but not carrying nukes. 
More photos capturing the great spirit at the demonstration in Washington DC today for Ukraine!
The report states that size of China’s stockpile probably surpassed 400 warheads in 2021, up from low-200s in 2020. sipri.org/sites/default/…
2/n - Unlike the generic nuclear threat issued at the start of his attack on Ukraine in February, this threat is explicitly linked to the military situation in Ukraine. And “when the territorial integrity of our country is threatened” goes beyond Russian declaratory policy. 
After reaching a point over Slovakia about 140 km from Ukraine border, the B-52 headed southeast over Hungary, turning east into Romania. 