THERE are decades when nothing happens, then weeks when decades happen. I’m not sure what Lenin, the author of that famous quote, would have made of the invasion of Ukraine. He was no slouch himself when it came to brutally suppressing opponents, though he claimed to support self-determination for Ukraine in 1920.

That aside, we are beginning to understand just how much the world has changed in the last seven days. Not just in geopolitics but in the cultural realm as well. We have become used to thinking of peace in Europe as a given. That defence budgets can be cut to the bone because no one would be stupid enough to start a war. Well, now we know.

The most obvious culture shock is German rearmament. This country has essentially been pacifist since the fall of the Third Reich. Now the Green/Social Democrat government of Olaf Scholz is throwing €100 billion at a new defence fund and sending arms to Ukraine. Neither of these would have been imaginable only a week ago. Germany is to become military power again.

Equally astonishing is the European Union becoming a de facto military alliance. It is sending lethal weapons to Ukraine including, it was suggested at the weekend, war planes. Until last week that would have been regarded by many as beyond Brussels’ powers. Yet the die has been cast.

The crisis in Eastern Europe is not going to go away any time soon. Whatever happens in Ukraine, and videos of convoys of Russian arms heading for Kyiv suggests that the end game has begun, security is now top of the European agenda.

Read more: Ukraine’s President and his people are giving the West a true lesson in bravery

Yes, even more now than Brexit. Petty squabbling over fish and border checks on sandwiches suddenly seem absurd and irresponsible. The countries of Europe, in and out of the EU, are now united in defence of democracy and human rights against Putin’s imperialism.

Many in Europe, not least the French, may be doubly anxious to mend relations with the second biggest military force in Europe: the UK. Continental European counties will be distinctly uneasy at German rearmament, whatever they are saying now. They haven’t entirely forgotten the last war

The European project was premised on globalisation – the idea that borders were irrelevant and essentially xenophobic. This has been the default position of Europe’s political and media elites for the last 30 years, though ordinary voters were never entirely happy about losing national self-determination to an unelected bureaucracy in Brussels.

Borders reasserted themselves somewhat during Covid. Now, following the Russian invasion, borders really are back, militant nationalism is back. When people face threats to their security they look to their national government for protection. From mighty Germany to tiny Estonia, national defence has returned as the paramount purpose of the state.

Read more: Europe’s foolish dependency on Russia's oil and gas

With rearmament, a new generation of young European men are going to be invited to enlist in national armies and learn to fight. No longer is war in Europe something you only see on grainy Netflix videos.

We are all going to have to relearn the language of popular militarism.

This not a language with which we are familiar or comfortable. We have tended to ridicule martial values when we don’t actually despise them as blood lust. We laugh at old buffers romanticising the last war. We’re beyond all that silly flag-waving nonsense,

aren’t we? Well, see how potent that blue and yellow flag has become. The Ukrainian people have shown just how powerful nationalism is when the chips are down. It can move people to acts of courage and self-sacrifice of which they never thought themselves capable.

But as the Scottish nationalist writer Tom Nairn always warned, nationalism is Janus-faced. It is always liable to slip into the dark side of xenophobia and nativism.

Those white nationalists in Kyiv that Vladimir Putin says are Nazis are fighting on the front line right now against Russian tanks. That they have been willing to fight for a Jewish political leader who used to wear high heels in pop videos suggest that they are not cultural Nazis. But they remain militant nationalists first and foremost.

Hell, when the Russians are at the gate you don’t look for political correctness, just the willingness to pick up a gun.

Nor do you ask people to check their pronouns or their white privilege. Ukraine is also an inflexion point in the identity and gender wars that have dominated Western culture in the last decade.

Traditional gender roles have reasserted themselves almost overnight in Ukraine. Many women have put themselves in danger on the front line, parading on social media with assault rifles, but it is the men who have been ordered not to leave. It is the men who are doing most of the fighting – with apparent willingness.

This doesn’t mean a roll-back for feminism or female rights, but it is significant. No one has ever worked out how you have a gender-balanced war. We have discovered that the antique virtues of stoicism, self-sacrifice and courage are needed once again. No one complains about toxic masculinity when it comes to killing Russian soldiers.

Fortunately, this does not portend a return to swaggering machismo and male arrogance. Volodymyr Zelenskyy’s is a new kind of martial courage. His very lack of machismo has become a source of national pride and strength. Ukrainians watch his dancing in their version of Strictly with undisguised glee, imagining what Botox-faced Mr Putin would look like on the dance floor. Of such things legends are made

So if nationalism is back, where does this leave Scottish nationalism? It’s a question for another time, but it is rather looking now like a fair weather phenomenon. Scotland is not an oppressed country, however much we complain about London dominance. Westminster is not Russia. Boris is not Putin.

We do not have to fight for our human rights. Scotland may well have decided to restore aspects of its economic independence. But it will always remain part of a democratic UK and a democratic Europe. We are all in this together.

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