The Kremlin responded with predictable theater to Foreign Secretary David Cameron's comments after he said Ukraine was free to use UK-supplied weapons to strike Russia, Chatham House wrote ; and "Independent".
That theater was both diplomatic, with Britain's ambassador summoned to the Foreign Office in Russia on Monday to warn of retaliation, and nuclear: Moscow announced it would hold tactical nuclear weapons exercises in the near future to remind to the world once more that they exist.
The UK's position is in stark contrast to that of the US, which has consistently banned Ukraine from using the weapons it supplies to strike targets in Russia. The US even dissuaded Kiev from doing so using its own capabilities.
Deployment in Ukraine
Britain has repeatedly taken the lead in supplying weapons systems such as long-range missiles or main battle tanks to Ukraine. In the process, it turned out that fears of "escalation" in Washington and Berlin stem from a highly successful Russian ploy.
But the UK's moral authority has been shaken in recent months by its reluctance to rearm its own armed forces in the way it is urging other European countries to do: grandiose defense investment announcements have proved inadequate on closer inspection.
Cameron also suggested that Britain's long-term commitment to support Ukraine will now be largely financial as "we've just really exhausted everything we can in terms of providing equipment.
And unfortunately, he immediately undermined the effect of even that commitment by once again ruling out the presence of Western troops in Ukraine.
French President Emmanuel Macron has repeatedly warned that European troops could be forced to intervene if Ukraine fails to stop Russian aggression. It is vital that Russia understands this, as the last thing Moscow wants is a direct military confrontation with NATO countries.
And yet other European leaders reacted with dismay to the proposal. "I don't think it's right for NATO soldiers to kill Russian soldiers," Cameron said at the end of his visit to Ukraine. That may be true today, but as Russia's ambitions become more apparent, it serves as a reminder that NATO's goal should be to stop Russian soldiers from being where they have no right to be.
In any case, publicly rejecting the presence of Western troops in Ukraine makes no sense, regardless of whether it is a realistic proposition for some NATO countries. This possibility alone is one of the Kremlin's greatest fears.
When Cameron and others publicly rule out this option, all it does is reassure Putin that he can continue the war with far less concern for the possible consequences.
Instead, more European leaders - and the UK - should follow Macron's lead and maintain "strategic ambiguity" (that is, don't tell your opponent what you won't do).
Russia steps up aggression
Over the past two weeks, Europe as a whole has woken up to the campaign of sabotage and disruption that Russia is waging across the continent. There is no doubt that Russia can step this up even further. Moscow's war against the West is now barely hidden, and as long as the West doesn't react, there aren't many obstacles for Russia to wage it.
The use of an extensive network of proxies means that the Kremlin's intelligence chiefs won't have to worry too much if they are caught red-handed. Scammers and fraudsters who hire overseas will be considered even more exploitable than their own staff. And since Russia is already openly acting as a rogue state, there is no reason to worry about damaging its reputation or relations.
The West should expect proxy attacks against the UK and all of Europe to continue. Besides hampering support for Ukraine, they have another useful purpose for Moscow. Whether they succeed or not, they are useful for gathering information about a country's will and capacity to prevent and respond to sabotage.
There is one traditional way of hurting the West that Russia may not have used yet. During the Cold War and even in Tsarist times, Moscow put effort and resources into sponsoring terrorist groups to carry out attacks on European cities. It would be a more indiscriminate campaign of violence than the targeting of European logistics and supporters of Ukraine that we are seeing now. It would also have a much greater impact.
Europe must not just be a passive victim. At the beginning of this year, we wrote about the underutilized ability of the West to influence Russia's choices.
The UK has made its Storm Shadow deliveries a clear consequence of specific Russian actions. Now, the US appears to have done the same with its long-awaited delivery of longer-range ATACM missiles.
It's no surprise to anyone, except maybe in the White House, that the sky hasn't fallen.
Britain's express approval of strikes against Russia can also be presented as a consequence of Russia's attacks on Europe and with the promise of more to come. Moreover, explicitly allowing Ukraine to strike Russia with British weapons as well as its own opens up other opportunities to target Russia's ability to wage war.
Ukraine has already struck Russian sites where drones and missiles used to kill its innocent civilians are stored. It also launched strikes on Russia's energy infrastructure. These limited pinpoint strikes are in stark contrast to Russia's ongoing campaign of indiscriminate bombing of Ukrainian cities.
But in further attacks, Ukraine could help Europe instead of the other way around. European countries can do little about Russian electronic warfare systems wreaking havoc on European air and sea traffic. But for Ukraine, no detentions should be prohibited, and it is in everyone's interest that the gagging be stopped or broken.
When considering how far the West should go in dealing with Kiev, the fundamental question remains the same: whether Europe wants to stop Russia in Ukraine or allow Moscow's war of expansion to take more casualties further west.
Simple morality and practical common sense have always been arguments for maximum possible support for Kiev. Britain's endorsement of Ukraine's right to defend itself is a long overdue step in the right direction.