The crisis, which has seen Russian troops mass on the Ukrainian border, is exposing differences between NATO members, with Germany even blocking the export of some weapons to Ukraine in recent days.

So what exactly is NATO and is Russia right to be worried about it?

The history

Russian demands

Russia has demanded that NATO guarantees Ukraine will never join the alliance, something the organisation couldn't realistically offer, according to Ed Arnold, a research fellow at the defence think tank RUSI.

He also believes the view that NATO is "encircling" Russia and posing a threat is misguided:

"Very little of Russia's landmass is actually bordered by NATO… which is fundamentally a defensive alliance. European nations don't really want to have to station troops in eastern Europe, as it's expensive.

"Russia's actions are more about trying to project itself as a great power again."

Even if NATO members don't want to have to supply troops and weapons, some have come to Ukraine's aid in light of the Russian build-up.

NATO's response

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Will the equipment make a difference?

Much of the weaponry sent comes in the form of anti-tank missiles. However, according to Sam Cranny-Evans, a military science analyst at RUSI, the weapons will have only a minor effect should Russia take action.

"Russia will likely conduct 'non-contact warfare' initially should they engage, meaning they will operate at long-range using cruise missiles and reconnaissance assets to find targets. NLAWs, the weapons the UK have provided, are only effective at around 800 metres - that's not going to deter Russia."

But the sending of weapons is likely to have a second effect - by signalling how committed some countries are in confronting Russia and shoring up NATO.

The German reluctance to grant the export of Estonian artillery would appear to show a divergence in this regard.

Some have pointed to the importance of Russian natural gas imports to Germany to explain this decision.

But Germany is not alone in failing to send weaponry. Canada has also declined, despite having supported Ukraine with over £500m of military training and humanitarian aid since 2014.

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These decisions may reflect differences of opinion over whether a show of force or de-escalation are the best ways to confront the Russian threat.

Regardless of how unified NATO members are, Ed Arnold is clear that the situation will leave lasting effects:

"There's going to be probably fairly major changes in the next couple of years due to this… NATO and the EU might sort themselves out once and for all, as Russia is the most acute threat to Europe since the Cold War and it's not going away."

Video credit: Cpl. Jeff Drew/Military Notes

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