Key Points
- From the war in Ukraine to North Korea's recent missile testing spree, tactical nuclear weapons are being debated.
- But what are tactical nuclear missiles and how are they used.?
From the war in Ukraine to , tactical nuclear weapons are being debated and developed in a way not seen since the Cold War.
There is no universal definition of such weapons, and analysts note that the use of any type of nuclear device would break the "nuclear taboo" in place since the United States dropped atomic bombs on Japan in 1945, the only time they have been deployed in war.
Here are the characteristics of tactical nuclear weapons and why they have drawn so much attention.
What makes a nuclear weapon 'tactical'?
Tactical nuclear weapons are often characterised by their size, their range, or their use for limited military targets.
They are often referred to as "non-strategic weapons", in contrast with strategic weapons, which the US military defines as designed to target "the enemy’s war-making capacity and will to make war," including manufacturing, infrastructure, transportation and communication systems, and other targets.
Tactical weapons, by contrast, are designed to accomplish more limited and immediate military goals that win a battle.
The term is often used to describe weapons with a lower "yield", or the amount of power released during an explosion.
They are typically many times larger than conventional bombs, cause radioactive fallout and other deadly effects beyond the explosion itself, and there is no agreed upon size that defines tactical weapons.
Tactical weapons are often mounted on as missiles, air-dropped bombs, or even artillery shells that have a relatively short range, far less than the huge intercontinental ballistic missiles (ICBMs) designed to travel thousands of kilometres and strike targets across oceans.
However, many of these delivery systems can also deliver strategic nuclear weapons.
What countries have tactical nuclear missiles?
Many of the world's nuclear powers have weapons that are considered low-yield or meant to be used on the battlefield.
According to a March report by the US, Congressional Research Service (CRS), the United States has approximately 230 non-strategic nuclear weapons, including about 100 B61 bombs deployed with aircraft in Europe.
In 2018 the Trump administration announced plans for a new low-yield warhead for submarine-launched ballistic missiles (SLBMs) and a new non-strategic nuclear-tipped cruise missile.
Russia has 1,000 to 2,000 warheads for non-strategic nuclear weapons in its arsenal, the CRS report says.
North Korea that its recent flurry of missile tests were designed to simulate showering the South with tactical nuclear weapons.
Experts believe that if North Korea it could include development of smaller warheads meant for battlefield use.
Will the missiles be used?
President Vladimir Putin, who rules the world's biggest nuclear power, has repeatedly cautioned the West that any attack on Russia could provoke a nuclear response.
U.S. President Joe Biden said on Wednesday he doubted that Putin would use a nuclear weapon, and analysts have said tactical weapons could have limited military use in the vast and dispersed battlefields in Ukraine.
Earlier Biden noted that the use of even small nuclear weapons could spiral out of control.
"I don't think there's any such thing as the ability to easily (use) a tactical nuclear weapon and not end up with Armageddon," he said last week.
North Korean leader Kim Jong Un watches a missile test at an undisclosed location. Source: Supplied / KCNA/Korea News Service via AP.
It has also prompted renewed debate in South Korea over redeploying American tactical nuclear weapons, which were withdrawn from the peninsula in the 1990s, or pursuing its own nuclear programme.
When will North Korea test a nuclear weapon?
Only North Korea knows. And observers say even within the country there is a good chance that only Kim or those around him have any idea of exact timing.
North Korea is a particularly difficult target for the US and other foreign spies, who have been caught off guard before by some of the country's advances, including its test of a suspected hydrogen bomb and launch of intercontinental ballistic missiles (ICBMs) capable of striking as far as the United States, both in 2017.
"We usually have a pretty good idea of their capabilities that we can detect from satellites or other technical intelligence, but so much comes down to what's in Kim Jong Un's mind. And that we don't really know," said one Western military official in Seoul, who declined to be named because of the sensitivity of the issue.
Satellite imagery has shown North Korea this year that were closed in 2018, when Pyongyang declared a self-imposed moratorium on nuclear weapons tests. Kim, however, has said he no longer feels bound by that moratorium, with denuclearisation talks stalled since 2019.
for a test could be between the Chinese Communist Party congress, which begins on 16 October, and the midterm elections in the United States on 7 November, South Korean lawmakers briefed by its spy agency said last month.
Other considerations that may guide Kim's thinking are the COVID-19 situation in the country, the war in Ukraine, local holidays, and signalling from partners in China and Russia, analysts said.
What would be the reaction to a nuclear test by North Korea?
The United States and its allies in Asia have vowed that a resumption of nuclear testing "would be met with a strong and resolute whole-of-government response", but have not elaborated. Missile tests have been met with unilateral sanctions and displays of military force, including joint drills and the deployment of a US aircraft carrier.
President Joe Biden has vowed a strong reaction if North Korea resumes nuclear tests. Source: AAP / Manuel Balce Ceneta
Those two countries more recent attempts to impose new security council resolutions, however.
Analysts say neither Beijing nor Moscow is likely to welcome a new test, but that they are unlikely to back any major new punishments.
"They probably wouldn't be keen on it. But I think that's less of an issue for them now than it was five or 10 years ago because of the nature of their relationship with the US," Van Diepen said.
