Editor's note: Jonathan Arnott is a former member of the European Parliament. The article reflects the author's opinions and not necessarily the views of CGTN.

I write these words as I wake up to what has seemed inevitable for some time. Russian President Vladimir Putin describes a "special military operation" in Ukraine, whilst Ukraine says that "Putin has launched a full-scale invasion of Ukraine." NATO and the European Union share a simple conviction: that Russia is the aggressor in this conflict. They side clearly with Ukraine.

It is a rapidly-changing situation. There are many "known unknowns," to borrow a famous Rumsfeld term: we cannot know for sure what Russia's long-term goals are with respect to Ukraine. Nevertheless, there are clues: it's possible to form an opinion.

In isolation, a full-scale war between Russia and Ukraine would likely end with a convincing victory for Russia: Russia's defense budget is roughly ten times that of Ukraine's. Russian tanks outnumber those of Ukraine, and Ukraine has limited defense against Russian air superiority.

But - for the time being at least - Russia has only committed a fraction of its armed forces to the border with Ukraine. Ukraine does have some Western-supplied arms to mount short-range defense against tank and air strikes. It is calling up military reservists, offering weapons to anyone who wants them, and demonstrates clear determination.

In short, it appears that Russia's goal is not a full-scale annexation of Ukraine. A defensive war is almost always easier to fight than gaining and permanently controlling territory. If Putin's current plan were to capture the whole of a country the size of Ukraine, he would have needed to commit far more troops to the border with Ukraine than he has done so far.

In my opinion, it is more likely that Russia intends a more limited operation: to separate out the Russian-speaking regions whilst utilizing long-range air superiority against military and strategic targets in the rest of Ukraine. Putin's brand is one of ethnic nationalism, and he is keen to take bold moves to achieve his aims.

To Putin, everything is time-sensitive. He takes risks, choosing decisive action. Putin makes assumptions: for example, that with U.S. President Joe Biden in the White House, America will be more cautious. He is a man in a hurry.

I have not yet mentioned economic sanctions by Western nations against Russia. Such sanctions will be costly for Russia in absolute terms, but nowhere near to the extent of limiting Russia's ability to wage war. In President Putin's mind, territorial considerations will always outweigh economic ones. It is a huge error to expect sanctions to change Russian actions. Sanctions can be effective against some nations under certain circumstances: if the behavior change demanded is relatively minor, and if the sanctions are against a much smaller nation, for example. That's not the case here though.

But the real danger of any war, like World War I, lies in gradual escalation. Ukraine may not be able to match the Russian army in absolute terms, but it does have the substantial overseas support and the firepower to put up considerable resistance. Where two nations both consider any area to be their own territory, they may be prepared to go to almost any lengths to defend their interests.

I therefore expect that Russia's long-term objective is to gain control, to put it simply, of Russian-speaking areas of Ukraine. The question is whether it can do that without utterly defeating the entirety of Ukraine by military means, and to do that it would require more troops than it currently has.

This leaves NATO and European Union nations with a dilemma. They can support Ukraine in the background, through donations of weapons and training. They can impose economic sanctions against Russia. None of these actions, however, are likely to fundamentally alter the situation. But Russia remains a strong enough global power with nuclear capability that there is little deterrent possible. Any direct military action, even aerial support, risks a substantial escalation.

Nobody knows for sure what will happen next. The risk of this conflict growing into a full-scale multi-national war is not huge. I do not expect such a scenario to occur, but we must admit that there is still a non-trivial possibility that it might. We live in highly uncertain times.

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