The discussion here has turned to tactical nuclear weapons. This post is in counterpoint to the claim that there are no such things. A statement regarding tactical nukes made by Secretary of Defense General James Mattis, and echoed by honorentheos, is quoted below. While one can agree with this viewpoint in terms of the possible political effects of their use, it is still a fact that, by definition, there are low-yield nuclear weapons designated as tactical or battlefield nukes - as described in this post.
SecDef James Mattis wrote: US secretary of defense James Mattis declared in 2018 “I don’t think there’s any such thing as a ‘tactical nuclear weapon.’ Any nuclear weapon used at any time is a strategic game changer.”
The US has approximately 100 of them. These are under US control and mainly deployed with our allies in western Europe (the Fulda Gap is still there). The Russians have a lot more.
As mentioned upthread, low-yield nukes (say under 10 kt.
* or so) were developed as tactical
defensive weapons during the early years of the cold war. Their original intended use was to delay or stop a massed armor attack from the Warsaw Pact across the central European plain via the Fulda gap.
As an example, one of the lowest yield of these on the American side was known as the Davy Crocket (image below). It could be set up and fired by a two-man crew and has a maximum yield of 0.02 kt.
*. It is no longer in US inventory.
It is generally recognized that low-yield or tactical nukes are defensive weapons for use on the battlefield. Tactical nukes can be fielded in the form of bombs, missile warheads, artillery shells, or mines. (For a time in the late 1960s, our USMC artillery unit was equipped with mobile 8-inch howitzers that were nuclear-capable.)
Nuclear 8-inch artillery rounds are no longer in inventory. They were deemed more trouble to manufacture, support, justify to the public, and use than they are actually worth in battle. These beasts (image below) have pretty much been phased out in favor of the slightly smaller bore 155 mm (6.1 inch) howitzers. Nuclear rounds for the 155 were phased out in 1992. Again, they just are not worth it in a modern military. To maintain reliability, nuclear warheads must be serviced periodically by sending the to a facility near Amarillo Texas, where they are partially disassembled, inspected, and have their nuclear material replaced. This process is not inexpensive.
As mentioned, the Russians still have a lot of tactical nukes - pretty much in keeping with their failure to modernize their military. When used as an offensive weapon, artillery is meant to clear or diminish enemy strength in the disputed area so that friendly infantry can move in, clean up, and hold the new territory. Problem is that the residual radiation from even a small nuclear blast takes time to subside. If it requires (lots of) special protective equipment to move into and occupy an area recently cleared with tactical nukes, what's the point?
As described in more detail in the article linked below for those interested, tactical nuclear weapons are not the nuclear winter-inducing, civilization-ending weapons that some seem to think. As an example, the explosion of improperly stored nitrate fertilizer in Beirut harbor in 2020 (image below) was equivalent to about 600 tons of TNT (0.6kt), which would be in the range of tactical nukes. Had it been a nuke, the smoke and dust you see in the image would be radioactive. What invading force would want to decontaminate and clean up such a mess before they could use their newly gained territory?
The chart below shows the mass to explosive yield ratio of atomic (nuclear) and hydrogen (thermonuclear) weapons. Little Man and Fat Boy were the two bombs dropped on Hiroshima and Nagasaki, respectively, in WW II. The yield of Fat Boy was 21 kt. Weapons currently in inventory are designated with red and yellow circles on the chart.
As a quick review of the effects of low-yield nuclear weapons, the LD-50 (50% of the exposed will die) for direct radiation exposure from a 1 kt. blast is one-half mile. At the high end of the tactical nuke range, the radiation LD-50 for a 10 kt. blast is about 3/4 of a mile
**. The effective blast radius and subsequent fall-out for a given yield depend, to an extent, on the altitude of the detonation. Fat Boy (21 kt) at about 2X the yield of a high-end tactical weapon, was detonated at 1,800 feet and had a blast radius of about one mile. The graphic below shows a comparison of low-yield nuclear weapon effects.
Of historical interest is the now-famous image below showing the detonation of the first atomic bomb - the 25 kt Trinity Test in New Mexico in 1945. The spikes extending from the bottom of the initial fireball are from the vaporization of the guy wires supporting the tower on which the device (the Gadget) was mounted.
Shown below is the aftermath of the Trinity explosion. The steel stubs in the ground are what is left of the metal tower structure on which the bomb was mounted. Unlike conventional chemical explosions that would have left a twisted rusted skeleton of the tower, the nuclear explosion simply vaporized it.
Notice the appearance of the soil and the fact that the ground is flat, level, and devoid of any features except shallow cracks out to the slight berm several hundred meters from ground zero. The sandy soil under the tower was melted by the blast and formed a new mineral known, quite fittingly, as "Trinitite".
Standing in the center of the image is General Leslie Groves, the Army Officer who managed the Manhatten project. There is a city park named after him in Richland Washington, the town most associated with the Hanford Atomic Works where nuclear materials for the bombs used in WW II were made. Robert Oppenheimer, generally recognized as the technical father of the atomic bomb, was also at ground zero the day that picture was taken. He is standing next to Groves and is recognizable by his signature headwear hiding his face.
Here is a link to an excellent European article on tactical nuclear weapons. The image above is used in that article.
https://taketonews.com/the-danger-power ... r-weapons/
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*The explosive force, or yield, of a nuclear weapon is expressed in terms of
thousands of tons of TNT equivalent or kilotons (kt.)
** The blast radius and radiation LD-50 do not scale linearly with yield. Electromagnetic field strength, radiation intensity, or power, fall off at a rate of 1/r^2 where r is the distance from the detonation.