There are three main ways this could come about. The first is that Russia is pushed out of Kherson Oblast and pushed all the way back to Crimea. Suppose Ukraine launches a counteroffensive to retake the peninsula. This will be a red line for Putin as Sevastopol is a port considered key to Russian national security. As the only warm-water port under Russian control, it allows their navy to operate in the Black Sea and the Mediterranean.

If Crimea is under threat of being liberated by Ukraine, this is by far the most likely scenario in which Russia will deploy nuclear weapons. To bolster this, not only is Crimea of key strategic interest to Russia, but it is also a geographic area that will force Ukrainian units into closer formations, making them more susceptible to tactical devices. It is most likely a matter of time, rather than a discussion of whether Ukraine will launch a Crimean offensive, with Kherson set to fall soon.

The second most likely situation for nuclear use is a rebellion or coup attempt within Russia itself. Putin shies away from any display of weakness. A coup attempt that fails will most likely result in the use of nuclear weapons in Ukraine as a display of strength by Russia. The target would most likely be more symbolic than tactical, as we would see if Crimea were under threat.

Several symbolic targets make the list, the chief one being Kyiv, but other major cities in Ukraine could be considered, and might also be crossed off. The second biggest target would be Lviv, but its proximity to Poland and distance from Russia make it an unlikely target, as the further a cruise missile needs to penetrate into Ukraine, the more likely it is to be intercepted. The use of an ICBM-class missile would provoke an immediate response from NATO. So Kyiv remains the target in an attempt to show power and demoralize Ukraine.

The difference between this option and the other is that the striking of a city is extremely likely to provoke an immediate NATO or US response against Russia. This will inevitably lead to a major series of escalations ending in a nuclear exchange between Russia and the West.

The third likely situation that Russia will use to excuse the use of nukes is if Ukraine begins striking targets within Russia itself. Such as Belgorod near the Ukrainian city of Kharkiv, which has already seen some operations and Russian accidents. Bringing the fight home to the invaders is likely to not play well in their media. Hardline commentators for state TV will demand an immediate and strong response despite the fact that they are the ones who invaded Ukraine.

A strike in Russia combined with combat losses in the South and East could result in a nuclear strike or even a nuclear explosion above Ukraine in an attempt to take out their electric grid and cripple any other equipment not prepared to withstand an EMP burst, which is most equipment. This is also the least likely scenario for nuclear weapons use, as it won't change much and will incur either direct NATO intervention or extreme levels of aid to Ukraine, such as long-range missiles and modern aircraft systems.

In any of these scenarios, it is likely that the use of nuclear weapons will dramatically alter the course of the war. While it is popular right now to fear-monger the use of these weapons imminently, it will remain a last-ditch effort by Russia. We are not currently in that territory for the war, as Russia can continue to fight for some time.

It is also important to note that chasing a diplomatic option to prevent the use of nuclear weapons will inevitably result in demands for Ukraine to compromise. This is unacceptable given Russia is the aggressor, babying them like they are the ones we should feel sorry for is frankly ridiculous. The only way Ukraine should stop fighting is by returning to the 2013 borders, with a defensive pact from the United States. So that if Russia tries again in a few years, the Americans will be compelled to defend them.

A diplomatic option remains off the table for now, though, as Ukraine has been unwilling to negotiate with Russia since the bombings of various energy infrastructures began 3 weeks ago. We are in dangerous territory, as the US and Russia lack a dedicated channel for de-escalation, as we saw during the Cold War between the Soviet Union and the US. It was announced days ago that a Russian jet mistakenly fired a missile at a Royal Air Force Rivet Joint aircraft, which collects battlefield intelligence of the war.

An accident that could lead to a new world war remains a real possibility. We must all hope for level-headedness and strength in our politicians. A big ask that might disappoint us in the end.