Russian President Vladimir Putin (Vladimir Putin, Putin) said he was ready to use nuclear weapon to defend Russian territory, which caused concerns that he might use small or "tactical" nuclear weapons in Ukraine.
US President Biden warned Putin that doing so would be the worst military escalation since World War II.
What is tactical nuclear weapon ?
Tactical nuclear weapons are small nuclear warheads and their delivery systems, used on the battlefield, or conduct limited strikes.
Tactical nuclear weapons are designed to destroy enemy targets in specific areas without causing large-scale radioactive contamination .
The smallest tactical nuclear weapon can be one thousand tons or less, that is, one thousand tons of TNT explosive equivalent, and the largest one can reach one hundred thousand tons of TNT explosive equivalent.
Russian soldiers and Iskander missile
strategic nuclear weapons are larger (up to 1 million tons) and can be launched from a longer distance.
As a comparison, the atomic bomb dropped by the United States in 1945 on Hiroshima was 15,000 tons.
What tactical nuclear weapons does Russia have?
According to US intelligence, Russia has about 2,000 tactical nuclear weapons.
Russia's tactical nuclear warheads can be placed on various types of missiles , which are usually used to deliver conventional explosives, such as cruise missile .
tactical nuclear weapons can also be fired from aircraft or ships - as anti-ship missiles , torpedo and deep-water bomb .
The United States said Russia has been investing heavily in these weapons lately to improve its range and accuracy.
Tactical nuclear weapons have been used before?
Tactical nuclear weapons have never been used in conflict.
Nuclear powers like the United States and Russia have found that using modern conventional ammunition to destroy targets on the battlefield is equally effective.
Furthermore, so far, no nuclear country is willing to risk a full-scale nuclear war while using tactical nuclear weapons.
However, Russia may be more willing to use smaller tactical weapons than the large strategic weapon .
"They probably don't think they are crossing this big nuclear watershed." Patricia Lewis, head of the international security program at the Royal Institute of International Affairs, believes that "they (Russia) may see it as part of their conventional forces."
Putin's nuclear threat is really worth worrying about?
In February 2022, shortly before the invasion of Ukraine, President Putin put Russia's nuclear forces in a "special state of war readiness" and held a high-standard nuclear exercise.
Recently, he added, "If the territorial integrity of our country is threatened, we will undoubtedly use all available means to protect Russia and our people. This is not a bluff."
After Russia occupied southern and eastern Ukraine, it is planning a referendum that is not internationally recognized to annex it. President Putin said he is ready to defend the "territorial integrity" of these regions "through all means."
US intelligence agencies believe this is a threat to the West, i.e., not trying to help Ukraine take back these territories, rather than indicating that Putin is planning a nuclear war.
But there are also concerns that if Russia suffers further setbacks, it may be unable to help but use smaller tactical weapons in Ukraine to "change the game" to break the deadlock or avoid defeat.
, a nuclear expert at the Carnegie International Peace Foundation in Washington, said, "I have reason to worry that in that case Putin may use nuclear weapons - likely to be used locally in Ukraine to intimidate everyone and achieve its purpose. We are not yet at that point."
How did the United States respond?
US President Biden has warned Russia not to use nuclear weapons in the Ukrainian war.
Biden first said in an interview with CBS News that this action would "change the situation of the war, unlike anything since WWII ", adding that "this will have consequences".
If any nuclear weapons are used, it is difficult to predict how the United States and NATO will respond. They may not want to risk a full-scale nuclear war to escalate the situation, but they may also want to draw a bottom line.
However, Russia may also be blocked by another major power, China, from the use of tactical nuclear weapons.
"Russia relies heavily on China's support," said Heather Williams, a nuclear expert at King's College London.
"But China has a principle of not using nuclear weapons first. So if Putin really uses nuclear weapons, it will be difficult for China to support him."
"If he uses them (nuclear weapons), he may lose China (support)."
