As feared, Russia’s so-called ‘special military operation’ in Ukraine was launched with widespread attacks, including near the capital Kyiv, using aircraft and missiles to disable airfields, combat aircraft and other military assets. Russian troops landed at Ukraine’s main port of Odessa in the southeast, and at Mariupol in the southwest, and parts of these cities have been under missile fire.

In the so-called rebel provinces of Luhansk and Donetsk, Russian troops crossed the border to support their local militia forces. Repeated cyberattacks have disrupted Ukrainian communications and critical infrastructure.

Russian tanks and heavy armour crossed the border from Belarus, a couple of hours of highway driving from Kyiv. Much further to the south, columns of armoured vehicles were filmed moving north from the Crimean Peninsula. They could help secure a land bridge to the eastern rebel provinces but are too far away to threaten the capital.

Russian special forces units are operating in Ukraine in significant numbers. Their task will be to degrade Ukrainian military assets to reduce opposition to the land assault. Special forces operatives may also be targeting Ukraine’s political leadership.

It’s clear that this operation is moving on a much bigger scale than simply consolidating Russian control of the eastern provinces. It is a large-scale attack, operating on multiple dispersed fronts and using all elements of Russian power: sea, air, land, rocket forces, special forces, and even mercenaries brought from Russian private ‘security’ activities in Africa.

The spread of attacks indicates this may be the largest military assault on an independent country in Europe since the fall of the Berlin Wall. As we know only too well from Iraq and Afghanistan, it’s easier for an aggressor to occupy a country than to stabilise it, and once the tanks are rolling there’s little option other than to press for military victory.

The next 48 hours or so will be decisive as to whether this attack will attempt to seize political control of the country, a move that will require a long-term Russian occupying presence, or simply peter out into a temporary exercise—in President Vladimir Putin’s words, to ‘demilitarise’ Ukraine. That strategic objective offers a convenient cover to withdraw if things start going badly for Moscow.

To use the words of the redoubtable former US secretary of defence Donald Rumsfeld, there are many ‘known unknowns’ about how this conflict might unfold in coming days.

Russian armour has been able to move towards Kyiv from Belarus along roads upgraded to improve economic links between that country and Ukraine. Belarus is where Putin has deployed some of his most capable forces, including the 76th Guards Air Assault Division, with a battle lineage going back to Stalingrad and modern combat roles in Chechnya, Georgia and the 2014 Crimean invasion.

Hitting Kyiv from the north was the obvious option for a lightning campaign to decapitate Ukraine’s political leadership, and yet so far we have a naval assault from the south and a broader air and missile assault.

We also don’t know about the likely extent of Ukrainian resistance. Russia’s Defence Ministry claims it has disabled all of Ukraine’s air defences and air bases. But will the Ukrainian army and reserve forces be able to get anti-armour weapons into action?

We should not assume that the Ukrainian military will fold as quickly as the Afghan security forces did. There is a terrible irony here. The Afghan military was built around the presence of US and allied forces providing intelligence support and critical maintenance of aircraft and vehicles. Afghan resistance collapsed not because key units didn’t want to fight; they just lost all their enabling support.

This is not the case in Ukraine, where Western military support has been deliberately limited since 2014 to avoid ‘provoking’ Russia. After eight years of fighting around the eastern rebel provinces, it’s likely that the Ukrainian military has the equipment and motivation to put up stiff resistance.

We also don’t know about the strength of opposition inside Russia to such a large-scale military operation, which, terribly, may soon be sending young soldiers home in body bags. This military operation is on a much larger scale than Russia’s recent air and special forces operations in Syria. It will take a much deeper bite from the Russian economy and affect many more families. It’s unclear how long Putin will be able to confect public support for a large-scale military occupation.

Here is one last ‘known unknown’: we don’t know what Chinese leader Xi Jinping really thinks about Putin’s actions. Rhetorically, the two dictatorships have each other’s backs. But Beijing’s language grew more cautious in recent days. If Russia’s invasion draws NATO and America’s friends and allies more closely together in a new cold war power divide, that won’t advance Xi’s goal for military domination.

In one sense, China wins from this conflict because Putin becomes more dependent on Xi. China will be Russia’s economic lifeline when (and if) sanctions bite and a long-term occupation of Ukraine will bleed Russia dry.

Just like North Korea, Beijing now has a second errant ‘little brother’, always plotting dire malevolence. But China wants to own the world order, not smash it like Putin. The conflicting world views of the two countries will keep them nervous about each other.

It’s too early for many lessons, but one is already clear. Western weakness in refusing to offer Kyiv any real military support handed Putin his opportunity. US President Joe Biden has had his second major foreign policy disaster after Afghanistan. He refused to lead, instead allowing a gaggle of Europeans to make separate and utterly fruitless pitches to Putin, asking him not to do what we could all see was about to happen.

NATO is nothing without the US. Biden could dismiss the fall of Kabul as a necessary evil so that America could concentrate on China, but there is no European exit strategy for Washington without handing central Europe to Putin.

For Biden, the lesson is that global security is not an elegant Ivy league politics seminar; it’s a knife fight in the dark, driven by animal instincts, blood and fear. Is Biden up for that fight with China? Are we?