Around 73% of Ukrainians now want their country to "restore" its nuclear weapons, according to a recent opinion poll. Most Ukrainians (58%) were in favour of their country owning nuclear weapons, even if it meant losing western allies.

This suggests an underlying regret that Ukraine agreed to relinquish the world's third largest nuclear arsenal as part of the Budapest Memorandum around 30 years ago. This agreement, signed in December 1994, provided security guarantees for Ukraine from the US, the UK and Russia in return for giving up the weapons. Ukraine also agreed it would not acquire nuclear weapons in the future.

The focus on nuclear weapons is intensifying all over Europe. This week the Polish president, Andrzej Duda, called on the US to station its nuclear weapons in his country to deter Russian attacks. He cited Moscow's decision to deploy nuclear weapons just across the border in Belarus during 2023 as part of his reasoning.

Trump's apparent weakening commitment to Nato has also prompted the French president, Emmanuel Macron, to suggest that France could extend protection of its own nuclear weapons to its allies.

It's clear that some Ukrainians now believe that their country would have been less likely to have experienced a Russian invasion if it had held on to its nuclear capacity. Ukrainians now question how much they can rely on other states after the failure of security guarantees that were central to the 1994 agreement.

The pledges by the US, UK and Russia to protect the sovereignty and independence of Ukraine were put to the test in 2014 when Russia invaded and then annexed Crimea and began providing financial and military backing for militia leaders in eastern Ukraine who claimed to lead pro-Russian separatist movements.

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The US and UK imposed economic sanctions against Russia and provided training, equipment and non-lethal weapons to the Ukrainian armed forces. But these measures fell well short of ensuring Ukraine's sovereignty and were insufficient to help Ukraine retake its territory.

Similarly, US and UK support for Ukraine since the start of Russia's full-scale invasion in 2022, although valuable and much appreciated by the Ukrainians, has not been enough to allow Kyiv to completely expel Russian troops from Ukrainian territory.

But what if Ukraine had never given up its nuclear weapons? The logic of deterrence suggests that Putin would have not have invaded and attacked a nuclear-armed Ukraine. But the argument that Ukraine should not have surrendered the Soviet nuclear weapons on its territory overlooks the specific circumstances. For while physical components of a nuclear weapons capability - delivery vehicles and nuclear warheads - were within Ukraine's grasp, the launch codes remained in Moscow, and Russian leaders showed no willingness to relinquish them.

So, Kyiv would have had no control over whether, when or against whom those weapons might have been used. The risk to Ukraine of becoming the target of another state's nuclear strike would have been considerable, and the Kyiv government would have been unable to do anything to reduce that risk. Retaining nuclear weapons left over from the Soviet period would have probably made Ukrainians less rather than more secure.

Read more: What is the value of US security guarantees? Here's what history shows

Ukraine also lacked the economic resources to maintain the nuclear weapons on its territory, or develop them into a credible deterrent force. In exchange for giving up nuclear weapons, Ukraine received much-needed economic assistance from the west.

In the 1990s Ukrainian views were shaped by the 1986 accident at the Chernobyl nuclear power plant. This had a devastating and lasting impact on the land and the people in that part of Ukraine, highlighting the risks of the nuclear sector. In 1994, when the Budapest Memorandum was being negotiated, only 30% of Ukrainians were in favour of Ukraine possessing nuclear weapons.

Ukraine would face considerable technical challenges in developing nuclear weapons today, both in creating the necessary quantities of fissile material for warheads and manufacturing delivery vehicles.

Kyiv would also need to pay for an expensive nuclear weapons development programme at a time when the Ukrainian economy is struggling to supply its soldiers with conventional weapons and meet the needs of civilians.

And unless Ukraine's international supporters were on board, Kyiv might face the withdrawal of economic and military aid at a crucial juncture. If Moscow detected any move on Ukraine's part to develop nuclear weapons, there would be a strong motive for a preemptive Russian strike to put an end to that plan.

But even though it may not be feasible for Ukraine to develop an independent nuclear deterrent in the short term, Kyiv may feel compelled to pursue a nuclear weapons programme unless Ukraine is provided with serious and reliable security guarantees. With the Trump administration apparently ruling out Nato membership for Ukraine, the onus is on the country's international supporters to come up with an alternative unless they want to see further nuclear proliferation in Europe.