In a speech on Friday, Putin railed against what he portrayed as a hypocritical and gender-mad West, including a transphobia rant about sex- change operations.

The Russian president is known for his attacks on liberals. Putin tried to intimidate Ukraine's allies by announcing that he was putting his country's nuclear forces on a heightened state of alert and warned that those who continued supporting Ukrainian armed resistance would face consequences they had never seen before.

There was a subtle threat compared to the ones made months later. Putin said that Russia's potential use of nuclear weapons was not a bluff.

The deputy chairman of Russia's security council, who was always eager to demonstrate his loyalty to Putin, said that Russia could use nuclear weapons in Ukraine.

NATO wouldn't dare respond and would risk a larger nuclear conflagration over a dying Ukraine.

The rhetoric could be seen as posturing from a country that is at risk of losing a war. Russia's reliance on nuclear blackmail is more explicit than ever, which is alarming to long-time observers. The United States dropped atomic bombs on Nagasaki and Hiroshima in World War II in order to set a precedent for the use of nuclear arms.

The director of the Nuclear Information Project at the Federation of American Scientists is HansKristensen. He spoke to Insider about the signs the US and others are looking for and why his latest speech is cause for alarm. Questions and answers have been edited to make them less long.

President Putin spoke about the annexation of eastern Ukraine. He made it clear that he would use all the means at his disposal to defend Russian territory. Is that implying nuclear weapons? Is anything he said different from what we know to be Russian nuclear doctrine? Is anything troubling?

It shows that he was more explicit last week. He likes to rattle this sword and be very dramatic, but of course the generic term, "all means at our disposal," could also mean many other things. It isn't known at this time. I think the key is that he's trying to create a new condition, in Russian declaratory nuclear policy, where just someone upsetting the integrity of Russian territory could be a recipient of a nuclear attack. The current declaratory policy is not the only one. That requires a lot more steps. He's trying to create a situation where there's more pressure on the West to stop fighting in order to get a negotiated settlement here.

If there's a threat to the state, they might resort to nuclear weapons, which is not so different to US doctrine. When you see Putin going a little more inflammatory, do you think he's playing politics or is he bluffing? Is that indicative of a change in their doctrine?

It is possible that it reflects a change in the way the president of Russia talks about this, but it is not certain. The Russian military knows what consequences throwing nuclear weapons around will have.

One could say this is what Putin does. He uses big words to scare other people. It'll take some time before we see if it's reflected in the actual planning they are doing. There are a number of steps that need to be taken before they can use a tactical nuclear weapon. He doesn't have a red button on his desk that he could press when he felt like it.

Is there anything that Putin could say that would alarm you more than just rhetoric? You would take the introduction of the code words into Putin's speeches as more than posturing.

I thought that was true. The use of nuclear weapons against Japan in World War II was one of the lines in his speech. "We're not the first doing this, the Americans have already done this type of stuff," he could argue. He's thinking about this in a different way, and that could add another level of indicator.

Max Seddon, the Moscow bureau chief for the Financial Times, commented on the speech today and he said that it was the most brutal attack on the West that he had ever heard. He said that if he were a Western policymaker he would be very concerned.

Do you think we should take a step back and not worry about nuclear weapons?

I think we should be extremely worried. I think it would take the conflict to a whole new level if this were to happen. We've heard statements from US officials that they've been trying to convey that for a long time and that the annexation of these territories by Russia seems to have made that even more urgent.

If we use a tactical nuclear weapon, they're not going to risk the existence of London, Brussels, New York City over poor littleUkraine. How could the West not say that it was not going to tolerate that?

The West wouldn't want to use nuclear weapons even if Putin used one. The use of a nuclear weapon by Russia andUkraine isn't an attack on NATO. It isn't an attack on the US. Is it possible for NATO to attack Russia with nuclear weapons if they haven't already done so? That's a tough issue and I don't think that's going to happen.

I think the outcome is more of a combination of diplomatic isolation, political isolation, cyber attacks, and possibly military action. Even that is hard to think about since NATO has not been attacked. There has been no attack on the United States. Are you going to attack Russia? That is a difficult problem to resolve. I think he's right when he says that. The danger is that the West can't really act at the nuclear level if Russia really thinks it can just pop a nuke there.

I don't want to see a war between two nuclear powers. It's hard to not say that they could get away with using a nuclear weapon when you talk about sanctions and diplomatic isolation.

If he did do it, it is possible that NATO or the US would conduct strikes against Russian forces inside of Ukraine. It wouldn't be an attack on Russia, but it would be considered an attack on Russia because they are Russian forces, if you will. If the Russians continued to do this, the next phase would be a lot more serious.

What is the difference between a tactical nuke and a non-tactical nuke?

The Cold War refers to battlefield weapons, where they were developed for wars involving nuclear weapons in a small area. The types of scenarios that were the center of planning during the Cold War were never looked at by arms control treaties because they looked at long-range strategic offensive forces.

The strategic arms control treaties don't cover tactical nuclear weapons. Most of the time it is shorter range systems that serve both nuclear and conventional roles. They have a wide range of yield options, from a single kiloton to tens of kiloton in some systems.

A Russian Tu-95 bear bomber and its escort fighter during an event in Russia.
A Russian Tu-95 bear bomber and its escort fighter during an event in Russia.
Photo by Elizaveta Becker/ullstein bild via Getty Images

When people talk about nuclear weapons, and the treaties that govern them, we tend to think about something that would cause an apocalypse, whereas these are to gain, to be obvious. Russia might be thinking about it because it would send a message.

All of those missions can be accomplished with strategic weapons. What kind of attack are you doing? The intensity of the attack. The Russians are because of their location. They are surrounded by potential adversaries in their area. NATO forces, as well as the Brits, the French, and the Chinese, are present. They need to engage those adversaries in those regions with regional nuclear forces.

Any use of a nuclear weapon is strategic in nature. The intensity of the attack and the range of it come into play.

The United States doesn't rely on tactical nuclear weapons as much as Russia because it doesn't have the same rights to fight nuclear wars as Russia. Most of the tactical nuclear weapons that were deployed in Europe and in South Korea were retired after the Cold War. It has a few hundred tactical nuclear bombs left for fighter jets, and some of them are in Europe, but it's not something it uses a lot for nuclear war planning. If the US had to respond lightly, they would rely more on strategic weaponry such as long-range cruise missiles and gravity bombs.

The use of a tactical nuclear weapon in Ukraine is being considered. The worse Russia is doing on the battlefield, the more likely it is that they will use a nuclear weapon against us. Is it possible to use a tactical nuclear weapon inUkraine?

There could be more than one of them. It is possible to try to turn the tide of the war by trying to knock out some of the Ukrainian forces that are needed to sustain their offensive. It would be a real battlefield use if you could say that, but it would take more than one weapon to have a real impact on the battle because you have to hit a number of areas and facilities. It might not be an advantage to detonating nuclear weapons in the field because it could rain over your troops as well.

The use of tactical nuclear weapons against Saddam Hussein's forces in the desert was considered by the Pentagon before the Gulf War. They discovered that they would have to use a lot of nuclear weapons to have an effect. Nuclear use is not always limited and benign.

There is battlefield interest. In terms of psychological effect, the other one is related, but they would use it against a few cities in order to break the will of the Ukrainians. Because of the human casualties involved, that would be considered a more significant attack.

They have to be careful about how they think about that because it could backfire politically by motivating the West to go in a different direction. There is a big problem with people inside the Russian system and the public in general if they think about tactical nuclear weapons as something small. To treat that as doable is a big problem.

Russian President Vladimir Putin (L), accompanied by Valery Gerasimov, the chief of the Russian General Staff, oversees the 'Vostok-2022' military exercises at the Sergeevskyi training ground outside the city of Ussuriysk on the Russian Far East on September 6, 2022.
Russian President Vladimir Putin (L), accompanied by Valery Gerasimov, the chief of the Russian General Staff, oversees the 'Vostok-2022' military exercises at the Sergeevskyi training ground outside the city of Ussuriysk on the Russian Far East on September 6, 2022.
MIKHAIL KLIMENTYEV/SPUTNIK/AFP via Getty Images

There's been a lot of talk of concern among US officials that Russia could potentially use nuclear weapons, and the US has been at least talking about increasing its monitoring of Russian forces. Is that what it means? The US and its allies are looking for something that could signal the use of a nuclear weapon.

There are a number of steps that the Russians have to go through to get what they want. The decision itself has something to do with that. Putin will have to agree with his military leadership about this. There are many theories about how the decision will be made. The red button on Putin's desk isn't the only thing. The chief of the armed forces, the minister of defense, and Putin are thought to be involved in this. If only one of them doesn't agree, then it's not possible.

If that is the case, it is very questionable. Even if they make a decision, they need to communicate it to the units that have to carry it out through the command and control system. It's possible that traffic is visible. The units that are activated are the ones that you get to first. Before you can fire a tactical nuclear weapons system, you need to get the warhead out of central storage. The special units that are the custodial units and the security units would be used. They would have to either use a truck or helicopter to get it to the front line. It would have to be installed by another team.

There are a number of steps that need to be set in motion in order for something to happen. Is the US turning up its intelligence gathering on this? It has been busy surveilling this for a while. Satellite observations include both the visible spectrum of satellites and also the visible spectrum of signals from satellites. There are spy planes flying all over the place. They've been working hard. They have been busy for a while. I think this is a normal level of activity. There are people on the ground. Some of the units that will relay information may have people in them.