The authors of the study estimated that as much as five million tons of soot could be released, producing a cooling of several degrees over large areas of North America and Eurasia (including most of the grain-growing regions).

This was described by the UK Parliamentary Defence Select Committee as "the launch of one or a limited number of missiles against an adversary as a means of conveying a political message, warning or demonstration of resolve".

American, French and British nuclear submarines are believed to carry at least some missiles with dial-a-yield warheads for this purpose, potentially allowing a strike as low as one kiloton (or less) against a single target.

Commodore Tim Hare, former Director of Nuclear Policy at the British Ministry of Defence, has described "sub-strategic use" as offering the Government "an extra option in the escalatory process before it goes for an all-out strategic strike which would deliver unacceptable damage".

[30] In many ways, this present change in the balance of terror can be seen as the complete embracement of the switch from the 1950s Eisenhower doctrine of "massive retaliation"[31] to one of "flexible response", which has been growing in importance in the US nuclear war fighting plan/SIOP every decade since.

Another possible nuclear terrorism threat are devices designed to disperse radioactive materials over a large area using conventional explosives, called dirty bombs.

President Harry S. Truman realized he could not afford such a horrendous casualty rate, especially since over 400,000 American combatants had already died fighting in both the European and the Pacific theaters of the war.

Before the development of a capable strategic missile force in the Soviet Union, much of the war-fighting doctrine held by western nations revolved around using a large number of smaller nuclear weapons in a tactical role.

Douglas MacArthur, an American general, was fired by President Harry Truman, partially because he persistently requested permission to use his own discretion in deciding whether to utilize atomic weapons on the People's Republic of China in 1951 during the Korean War.

The exercise, under the code name of "Snowball", involved the detonation of a nuclear bomb about twice as powerful as that which fell on Nagasaki and an army of approximately 45,000 soldiers on maneuvers through the hypocenter immediately after the blast.

The US military gave missile development programs the highest national priority, and several spy aircraft and reconnaissance satellites were designed and deployed to observe Soviet progress.

By comparison, smaller scale civil defense programs were instituted in the United States starting in the 1950s, where schools and other public buildings had basements stocked with non-perishable food supplies, canned water, first aid, and dosimeter and Geiger counter radiation-measuring devices.

By the late 1960s, the number of ICBMs and warheads was so high on both sides that it was believed that both the United States and the Soviet Union were capable of completely destroying the infrastructure and a large proportion of the population of the other country.

On September 26, 1983, Stanislav Petrov received convincing indications of an American first strike launch against the Soviet Union, but positively identified the warning as a false alarm.

Israel responded to the Arab Yom Kippur War attack on 6 October 1973 by assembling 13 nuclear weapons in a tunnel under the Negev desert when Syrian tanks were sweeping in across the Golan Heights.

[74] On 24 October 1973, as US President Richard Nixon was preoccupied with the Watergate scandal, Henry Kissinger ordered a DEFCON-3 alert[dubious – discuss] preparing American B-52 nuclear bombers for war.

[75] By the late 1970s, people in both the United States and the Soviet Union, along with the rest of the world, had been living with the concept of mutual assured destruction (MAD) for about a decade, and it became deeply ingrained into the psyche and popular culture of those countries.

It was believed (until the 1970s) that a Soviet tank offensive into Western Europe would quickly overwhelm NATO conventional forces, leading to the necessity of the West escalating to the use of tactical nuclear weapons, one of which was the W-70.

By comparison, the largest volcanic eruption in recorded history when the volcano Mount Tambora erupted in 1815—turning 1816 into the Year Without A Summer due to the levels of global dimming sulfate aerosols and ash expelled—it exploded with a force of roughly 33 billion tons of TNT or 33,000 megatons of TNT this is about 2.2 million Hiroshima Bombs,[80] and ejected 175 km3 (42 cu mi) of mostly rock/tephra,[81] that included 120 million tonnes of sulfur dioxide as an upper estimate.

It is quite possible that his actions prevented "World War III", as the Soviet policy at that time was immediate nuclear response upon discovering inbound ballistic missiles.

[citation needed] As a consequence of the September 11 attacks, American forces immediately increased their readiness to the highest level in 28 years, closing the blast doors of the NORAD's Cheyenne Mountain Operations Center for the first time due to a non-exercise event.

But unlike similar increases during the Cold War, Russia immediately decided to stand down a large military exercise in the Arctic region, in order to minimize the risk of incidents, rather than following suit.

NATO has stationed about 480 American nuclear weapons in Belgium, the Netherlands, Italy, Germany, and Turkey, and several other nations are thought to be in pursuit of an arsenal of their own.

[97] After nuclear weapons construction was started by President Zulfikar Ali Bhutto's command, the chair of Pakistan Atomic Energy Commission Usmani quit in objection.

Another potential geopolitical issue that is considered particularly worrisome by military analysts is a possible conflict between the United States and the People's Republic of China over Taiwan.

[116][117] In October 2018, the former Soviet leader Mikhail Gorbachev commented that U.S. withdrawal from the Intermediate-Range Nuclear Forces Treaty is "not the work of a great mind" and that "a new arms race has been announced".

Journalist Dmitry Kiselyov listed the targets in the United States, which includes The Pentagon, Camp David, Fort Ritchie, McClellan Air Force Base, and Jim Creek Naval Radio Station.

[126] On April 14, The New York Times reported comments by CIA director William Burns, who said "potential desperation" could lead President Putin to order the use of tactical nuclear weapons.

Naturally, shielding the entire body from high-energy gamma radiation is optimal, but the required mass to provide adequate attenuation makes functional movement nearly impossible.

Because 50% of the body's supply of bone marrow is stored in the pelvic region which is also in close proximity to other radio-sensitive organs in the abdomen, the lower torso is a logical choice as the primary target for protection.