Night City Holocaust

The Night City Holocaust, also known as the Arasaka Headquarters Bombing or AHQ Disaster, was a nuclear disaster in Night City that occurred on August 20, 2023.

Background
On August 20, 2023, a Militech incursion team led by Morgan Blackhand and Johnny Silverhand attempted an infiltration mission to steal/destroy the Arasaka Secure Reliquary Database inside the Arasaka Towers in Night City. During the assault, an area denial nuclear device, or "pocket nuke" was planned to be detonated in the building, with the planned area to absorb the impact of the blast and prevent massive destruction. However, due to interference by Arasaka and Adam Smasher, the nuclear device prematurely detonated on the 120th floor of the southern tower, 366 meters above the ground, obliterating Corporate Plaza and a large portion of Central NC, scattering radioactive fallout across the rest of Night City. The blast instantly incinerated over 12,000 people in the vicinity of the Arasaka Towers and fatally injured upwards of half a million more. Another quarter million died in the resulting aftermath over weeks and months. Hanako Arasaka cites the initial death toll was around four thousand Arasaka employees and Night citizens.

In the public's eyes, the reasoning for the nuclear detonation is never uncovered. Some believe it was Militech's overzealous desire to crush Arasaka, while others believe it was an area denial weapon meant to protect the Arasaka Towers.

Within hours, then–US President Elizabeth Kress nationalized Militech through the expedience of their CEO, General Donald Lundee, and his reserve commission. Militech was placed thoroughly under the control of the still sizable United States military, and banished all Arasaka forces from the continental US under the threat of a retaliatory strike on Arasaka's Tokyo headquarters. Other nations swiftly followed the US's lead, nationalizing and/or interdicting assets of both participants of the War.

Development
Mike Pondsmith commented about the nuke on Reddit:
 * Word of God Here: Ah, The Nuke. I spent way too much time with fallout and destruction tables to make sure this worked. To save making you guys read all that (40+ pages), I'll sum up. The suitcase nuke was based on a prospective terrorist bomb concept, which was about .5Kt. I used San Francisco as the target model, siting the blast at about Coit Tower. It went off halfway up the Tower, which absorbed the blast and put it around 1200 feet up. The Towers were surrounded by equally huge and tall structures that absorbed much of the initial shock wave (and fell outwards, causing much of the secondary destruction, but limiting the scale of impact). The Nuke was a "clean" device, so radioactive fallout was minimized ( the point was to wreck the Arasaka database, not the City). About 15K were instantly killed in the blast, with upwards of 100K dying over time from aftereffects like radiation, firestorms, building collapse... As I was doing this research and using fun tools like Alex Wellerstein's Nuke Map site (https://nuclearsecrecy.com/nukemap/), I seriously expected the feds to kick in RTG's doors and arrest the lot of us.