​The nuclear triad is a US military concept whereby the US can respond to a possible nuclear attack in several ways: by launching nuclear missiles from submarines hidden in the oceans, from fixed mines on the ground, or by launching nuclear weapons from strategic bombers in flight. All three components are on constant alert and can respond to a nuclear attack within minutes, which should, in theory, deter any attempt to attack the US.

At the same time, it is assumed that a possible attack on the USA (conventional or nuclear) cannot deactivate all three components of the triad: although the silos have known positions, they are built in such a way as to withstand nuclear explosions (buried in the ground, distant from each other), but the response to such an attack can come very quickly from submarines and bombers, whose positions are constantly changing and therefore cannot be hit by enemies, at least not simultaneously. It’s an architecture designed, as I said, to deter an enemy attack, and that doctrine was probably what prevented nuclear escalation during the Cold War.

According to a recent study (Nuclear Notebook), the United States has deployed approximately 1,770 active nuclear warheads, of which 1,370 are mounted on ballistic missiles and 300 are stored at strategic US military bases ready for use. 100 nuclear bombs are located at NATO air bases in Europe. Another 1,938 nuclear warheads are stored at various military bases for “dark days,” meaning they are inactive but can become active if the situation warrants, bringing the number of active nuclear warheads available to the U.S. in 2023 to approximately 3,708. These, in addition to more 1,536 decommissioned warheads awaiting dismantling that were transferred by the military to the Ministry of Energy.

The current land-based component of the nuclear triad is represented by approximately 400 intercontinental ballistic missiles Minuteman III (LGM-30G), housed in as many bunkers located in the states of Wyoming, Montana and North Dakota. They entered service in the 1970s, replacing the older Titan II (LGM-25C) missiles. Unlike Titan IIs, which used liquid fuel, Minuteman IIIs are equipped with solid-fuel engines, which makes their long-term storage in bunkers much more efficient and safer.

In order to launch in just a few minutes, the Titan II rockets must be fueled at all times, but since it is a liquid fuel, at low temperatures this aspect creates many logistical difficulties. Solid fuel solves these problems, allowing long-term storage of the rocket in a bunker and its launch in a short time (a few minutes) after receiving the order.

An intercontinental ballistic missile is a missile equipped with a nuclear warhead, which after launch performs a parabolic flight, leaves the Earth’s atmosphere, but does not go into orbit, but re-enters the atmosphere and hits the target, launching one or more nuclear missiles. warheads. If the Titan II was equipped with W-53 warheads (9 megatons, the largest in the history of the military), the current Minuteman IIIs are equipped with W-78 warheads (“only” 350 kilotons) or W-87 (about 300). kiloton). Although they seem less destructive, the Minuteman III is much more accurate than the Titan II. And since the Minuteman IIIs have been in use for more than half a century, the United States wants to replace them with new missiles.

There are voices that deny the effectiveness of the system of launching nuclear weapons from underground silos: the enemy knows his position and will be the first target in the event of a nuclear conflict. In addition, although they are 50 years old, Minuteman III missiles are no less effective and destructive. However, the US Air Force (the branch of the military that has nuclear mines and strategic bombers) has recognized that it is more efficient to replace them than to maintain them. The program was originally called GBSD (Ground Based Strategic Deterrent), but was recently renamed Sentinel.

The new Sentinel intercontinental ballistic missiles (LGM-35) are designed and manufactured by Northrop Grumman and will replace the Minuteman missiles in mines in Wyoming, Montana and North Dakota between 2029 and 2075. The engines for these rockets are being developed by Aerojet Rocketdyne (recently acquired by L3Harris) and will continue to use solid fuel. The Sentinels will be equipped with W-87 warheads inherited from the Minuteman-III.

Northrop Grumman has already received $13.3 billion to develop these missiles, and it is estimated that the cost of the Sentinel system will reach $1.5 trillion by 2075, and this is because not only the missiles will be replaced, but also the mine installations. will be modernized, and for the first time since the Cold War, the US will produce new nuclear warheads. And he will do it in the same laboratory at Los Alamos where J.R. Oppenheimer led the team that produced the first ever nuclear bombs.

The modern nuclear warhead used in modern intercontinental ballistic missiles is actually a thermonuclear bomb. It contains a plutonium core that is compressed by a classic chemical explosion to trigger the first phase of a nuclear fission reaction (similar to the nuclear bomb used in Nagasaki). But the enormous energy obtained as a result of fission is used to activate the second part of the bomb, which contains deuterium and tritium (isotopes of hydrogen), and which, under the enormous pressure created by the fission process, will melt and form helium, releasing the following, an even greater amount is spent on this process energy

But not only intercontinental ballistic missiles are being upgraded: a few days ago the first flight of the B-21 Raider bomber took place, which will gradually replace the current B-2A Spirit strategic bombers and which will be used together with the venerable B -52 Stratofortress (used since 1955 and will be used after 2040 year, according to current plans).

We cannot undo the discovery of nuclear fusion and fission, nor can we undo the invention of nuclear weapons. While limiting them in the future is possible, a world without nuclear weapons is probably an impossible aspiration. We can only learn to live with nuclear weapons and hope they are never used, even when tested. Although in the current context, they are increasingly talking about the resumption of nuclear tests by major powers.

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Photo source: Claudiu Tănăselia