The beta of Fallout 76 has ended, but streamer FrenchTomahawk actually managed to reach the endgame and fire an atomic missile in the last phase. This is what happens when a nuke strikes.
On the night of November 8 to 9, the last phase of the Fallout 76 beta took place. Although the beta was only available in several phases that lasted a few hours, streamer FrenchTomahawk made it to the endgame.
In doing so, he reached a high level and even managed to gather enough codes for firing an atomic missile. He was assisted by friends and the Twitch chat.

Atomic bomb strikes – This is what happens next
This is the effect of the impact: After the big explosion, the area darkens, and the light turns dark orange. Lightning flashes across the sky, creating a gloomy atmosphere.
It resembles the storms in Fallout 4 that can appear repeatedly and raise the radiation level. Otherwise, not much changes; the impact has no physical effects on the game world.
You can see that FrenchTomahawk is already beyond level 50 (you only receive skill points up to level 50). This is impressive as none of the beta stages were really available for long. Whether he could have used any exploits to achieve this is not known.
You can watch the missile strike in this video.
This is what atomic missiles are good for in Fallout 76
Nukes are part of the endgame in Fallout 76 and are actually not that easy to launch.
What is the purpose of these nukes? If you fire an atomic missile at an area, it will be temporarily highly irradiated. During this time, particularly tough enemies spawn, and there are rare resources to collect and better loot to find. Players feared beforehand that it would rain atomic missiles, but that should not be the case.
This is what you need to do to fire an atomic missile: There are several missile silos in the game world that are locked with codes. You need to collect and decode these codes. Some enemies that you randomly encounter in the game world carry these code fragments with them.

Apparently, nukes are also part of the main story, as Bethesda vice president Pete Hines suggested ahead of time.
It is quite possible that this atomic missile may not be the only one fired during the beta. Whether this was intended by Bethesda at such an early stage remains open.