As the war in Ukraine continues one question seems to be coming up repeatedly, will Russia use its nukes? Russia recently aired a video on state TV depicting a simulation of the detonation of nuclear weapons in the UK and Ireland. Although it is never calming to see another country threaten a nuclear attack it is almost certain that this video was aired as propaganda and not because Russia is genuinely planning to nuke the UK. It is highly unlikely that Russia will detonate a nuclear weapon during its war with Ukraine for several reasons.
One of the most obvious reasons is that should Russia detonate a nuclear weapon in Ukraine it may face nuclear repercussions. Although Ukraine itself does not have any nuclear weapons some countries supporting it do. It is also unlikely that Russia will engage in a nuclear attack against any countries supporting Ukraine, like the UK for example, because they do have nuclear weapons and therefor have second strike capabilities.
If Russia were to detonate a nuclear weapon in this war, no matter where it was detonated, the world would be entering into another period like the cold war. There would be much mistrust between the United States and Russia and the countries would constantly be skeptical of one another. As Russia has proved that it will be the aggressor in countries like Ukraine a new cold war would likely involve countries besides Russia and the United States. Other European countries would be wary of Russia due to proximity and their invasion of Ukraine and would arm themselves in case of attack. This could potentially create a more volatile situation than was seen in the first Cold War.
Another issue that would face Russia if they used a nuclear weapon would be international backlash. Many countries around the world have come to the conclusion that nuclear weapons are too dangerous and costly to use in modern warfare, the use of one could lead to full scale nuclear war. If Russia were to detonate a nuclear weapon while at war with Ukraine it would become an international pariah. Many countries around the world would break relations with Russia and they would be placed under heavier sanctions than they are now. This means the use of a nuclear weapon would be very detrimental to the Russian economy as well as Russian foreign policy.