South Korea has the economic, scientific, and industrial potential to quite rapidly develop nuclear weapons.
In the spring of 2022, the country began discussing withdrawing from the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and developing a nuclear program. Three factors played a decisive role: Russia's invasion of Ukraine, North Korean nuclear policy changes, and U.S. domestic political shifts.
According to Seoul (as well as Pyongyang, by the way), Russia's attack on Ukraine became possible because Ukraine decided to give up nuclear weapons. The South Korean press emphasizes that the presence of atomic weapons in Russia has formed a false idea of impunity for aggression in the Kremlin and has forced the West behave cautiously in this situation.
The second factor is changes in the North Korean nuclear program, which until 2015-2016 was defensive. In recent years, Pyongyang has been actively working on developing tactical nuclear weapons, even though North Korea already has intercontinental ballistic missiles capable of hitting targets in the United States.
Thirdly, the four years of the Donald Trump administration included statements from Washington about the possible withdrawal of the U.S. contingent from the Korean Peninsula, which would suddenly leave Seoul vulnerable.
The current U.S. administration of President Joe Biden is trying to restore confidence in the United States. However, North Korea’s nuclear arsenal virtually eliminates South Korea's advantage in conventional weapons. Only nuclear weapons are guaranteed protection against possible aggression by the DPRK against the South.
The critical impediment on the way to South Korea creating a nuclear arsenal will be the reaction of China and the United States. It is unlikely that Beijing or Washington will support such an initiative: China would consider South Korea's nuclear weapons a threat to its national security, and the United States is not interested in further discrediting the nuclear non-proliferation regime and nuclear militarization of East Asia. Seoul is also afraid of sanctions.
Yet despite these external factors, public support for obtaining nuclear power status within the country is high: polls show that over the past 15 years, the level of support among South Korean citizens has ranged between 60-75%