Is Putin ready to reach for the nuclear button?
So what will Russia do now? Will Vladimir Putin really reach for the red button?
In theory, he could. After approving changes to Russia's nuclear doctrine earlier today, he now has that option.
In what was a thinly veiled warning to the West, he lowered the threshold for a nuclear strike, allowing Moscow to respond with nukes if it's attacked by any state using conventional weapons. That includes missiles, aircraft, even drones.
In short, US missiles fired by Ukraine meet the new criteria.
Ukraine war latest: Ukraine launches six US long-range missiles at Russia, Moscow says
Please use Chrome browser for a more accessible video player
Moscow now also formally considers an assault on its territory by a non-nuclear power (read Ukraine) that is supported by a nuclear power (read America) to be a joint attack.
We knew these changes were coming. Moscow proposed them in September. But the timing of today's presidential stamp of approval appears deliberate, coming just two days after the US gave Ukraine permission to fire American arms deep inside Russia.
It's unclear if Mr Putin was aware of the Bryansk attack or not, which Moscow claims involved six ATACMS ballistic missiles.
The Ministry of Defence issued their statement after he signed off the new doctrine. But whether he knew or not, he must have known it wouldn't be long before an American missile landed in Russia.
It's not the first time we've heard these threats.
And now, after months of weighing them up, Washington is finally calling Moscow's bluff.
There are compelling reasons as to why Russia won't follow through.
Its main ally, China, won't tolerate it for starters.
More importantly, though, Moscow is unlikely to risk incurring the wrath of the new White House administration.
The signs so far are that Donald Trump will stick to his promise and pursue a swift conclusion to the conflict, which would likely be in Russia's favour.
Read more:
Where do Russia and Ukraine stand militarily now?
Why UK missiles would only have marginal effect on Russia
Spreaker This content is provided by Spreaker, which may be using cookies and other technologies. To show you this content, we need your permission to use cookies. You can use the buttons below to amend your preferences to enable Spreaker cookies or to allow those cookies just once. You can change your settings at any time via the Privacy Options. Unfortunately we have been unable to verify if you have consented to Spreaker cookies. To view this content you can use the button below to allow Spreaker cookies for this session only.
???? Listen to Sky News Daily on your podcast app ????
Launching a nuclear weapon now would almost certainly derail that.
But there is always a chance, of course, that Russia could do the unthinkable. After all, few predicted the full-scale invasion which started this crisis.
One thousand days on, the stakes are even higher, and the West is once again hoping it's interpreting the signs correctly.
