They are rattling nuclear weapons: It will have terrifying consequences...

But anger is being expressed openly in the Russian media, where pro-Kremlin pundits and bloggers are seething with calls for retaliation, even nuclear retaliation.

"This is not just an excuse, but a reason to launch nuclear strikes on Ukraine," said prominent bloggers Two Majors on their popular Telegram channel, which has over a million subscribers.

"After the mushroom cloud appears, you can think about who lied, made mistakes and so on," they added, referring to the Kremlin's inevitable search for scapegoats for the fiasco.

At least one prominent Russian political analyst, Sergei Markov, urged caution, warning in a social media post that the use of nuclear weapons would "lead to real political isolation."

But the popular blogger Alexander Kots demanded that we should "hit Russia with all my might, regardless of the consequences."

Of course, Russian hardliners routinely demand the nuclear annihilation of Ukraine, while at the same time making thinly veiled but ultimately empty Armageddon threats directed at Western allies. The fact that they are doing it again, after such a painful series of attacks, is not surprising.

But it would be a mistake to become too complacent and dismiss any Russian nuke-rattling as mere propaganda.

In fact, there are some troubling reasons to take the small possibility of a devastating Russian response a little more seriously this time around.

First, several Russian experts commented that Ukraine's destruction of a significant number of Russian strategic nuclear bombers could be interpreted as a violation of Moscow's legal nuclear threshold.

The Kremlin's recently updated nuclear doctrine - which sets out the conditions for a launch - states that any attack on "critically important" military infrastructure that "impedes the response actions of nuclear forces" could trigger nuclear retaliation.

The Ukrainian operation was a "nuclear attack loft," said Vladimir Solovyov, a fiery host of Russian state television, calling for attacks on the Ukrainian president's office in Kyiv and beyond.

Regardless of the legality, the bar for a Russian nuclear response remains mercifully high, and such a strike is likely to be dismissed in Kremlin circles as an impractical overreach.

For starters, it would poison relations with key Russian trading partners like China and India, as well as trigger potential military action against Russian forces.

The inevitable mass casualties would certainly arouse general scorn, further isolating Russia on the international stage.

But here's the problem: The Kremlin may now feel enormous pressure to re-establish deterrence.

It's not just Ukraine's recent drone strikes deep inside Russia that have humiliated Moscow. Soon after, Ukraine launched another audacious attack on the strategically important Kerch Bridge linking Russia with Crimea - the third time the vital road and rail link has been hit.

Shutterstock/Tommy Daynjer

The seizure of the Kursk region in western Russia by Ukrainian forces last year dealt another blow, leaving the Kremlin in a difficult position to liberate its own territory. Meanwhile, weekly, if not daily, drone attacks on Russian energy infrastructure and airports continue to cause widespread disruption far from the front lines.

At the same time, Ukraine's allies are gradually lifting restrictions on the use of Western-supplied weapons against Russia, further challenging what were once considered Moscow's red lines.

Few doubt that the Kremlin wants to respond decisively, but how?

A former Russian minister told CNN that Moscow's most likely response would be "barbaric" conventional missile and drone attacks on Ukrainian cities, which the people of Ukraine have been enduring for years.

"There is no other way, because Russia does not have the capacity to launch a massive military offensive. They do not have enough manpower for that," said Vladimir Milov, a former deputy minister of energy who now lives outside Russia.

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"People are talking about the potential use of nuclear weapons and so on. I don't think that's on the table. But, again, Putin has shown many times that he resorts to barbarism and revenge."

In other words, it is highly unlikely, but the nuclear option cannot be completely ruled out. This Ukrainian conflict has already experienced several unexpected twists and turns, not least the full Russian invasion itself in 2022.

And while Ukraine and its supporters are enjoying stunning successes in recent military operations, poking a humiliated and wounded Russian bear can have dangerous and terrifying consequences.