The war reaches Earth
The plot begins in Captain America #398 (March 1992) with the kidnapping of Rick Jones by Shi'ar agents intent on recovering Kree artifacts to aid them in the construction of a superweapon. In the course of rescuing Jones, Captain America discovers that a conflict has begun between the alien Kree and Shi'ar empires.
In Quasar #32 (March 1992), Captain America's fellow Avenger, Quasar, discovers that the use of a nearby stargate by the warring factions is destabilizing Earth's Sun. The Avengers gather and resolve to intervene in the conflict to try to ensure the safety of their solar system, either by bringing about a truce or by diverting the two empires from using the nearby stargate.
The Avengers assemble
In Avengers #345 (March 1992), a gathering of over twenty Avengers is divided into three teams to deal with the threat. One team stays on Earth to protect the planet for the duration of the conflict, while the other two are sent to the Shi'ar and Kree homeworlds via the Stargate to attempt to negotiate with the leaders of the two empires.
The "Earth team" is led by the Wasp and includes the Falcon, Hank Pym, Gilgamesh, Mockingbird, She-Hulk, Spider-Woman, and U.S. Agent. Quasar, Her, and Binary also remain in the Solar System to guard the stargates.
The "Shi'ar Team" is led by Captain Marvel and includes Living Lightning, Scarlet Witch, Starfox, Thor, Vision, and Wonder Man.
Finally, the "Kree Team" is led by Captain America and includes Black Knight, Crystal, Goliath, Hercules, Iron Man, and Sersi.
In the story, U.S. Agent is initially assigned to the "Kree Team," and Hawkeye to the "Earth Team." However, Clint Barton (Hawkeye's real identity) perceives this as a slight and is given Pym Particles to re-assume his Goliath identity.
This is one of the story's few overt references to the original "Kree-Skrull War" storyline, as Barton also appears as Goliath in that storyline (a fact which Barton and Pym comment on in the story).
The Kree-Shi'ar War
The Kree and Shi'ar Avengers teams go on to encounter various factions (including their super-powered teams, Starforce and the Imperial Guard, respectively). They are largely unsuccessful in engaging them in negotiations. Captain America's team are repeatedly captured and imprisoned by the Kree authorities while Captain Marvel's team engages in several short battles with various Shi'ar forces.
During the course of these encounters, it is revealed that the Shi'ar created a massive super weapon—the "Nega-Bomb"— using Kree artifacts. This bomb is capable of devastating an area equivalent to that of the Kree Empire.
Also, during the conflict, the Kree's military leaders are assassinated by the Shi'ar agent Deathbird, the Supreme Intelligence regains (temporary) control of the Kree forces, and Skrull agents are revealed to be surreptitiously manipulating the court of Lilandra Neramani into escalating the conflict.
Eventually, Captain Marvel's Avengers delegation manages to convince Lilandra to initiate peace negotiations with the Kree. However, by this point, the Nega-Bomb has been stolen by Skrull agents and her efforts to recall the weapon fail.
Despite the presence of Avengers members Wonder Man and the Vision in the Nega-Bomb's massive interior, the device is successfully detonated in Wonder Man #9 (May 1992). The Kree Empire is devastated by its effects, with billions dying instantaneously.
In Avengers #347 (May 1992), the various Avengers gather on Hala, the Kree homeworld, and discover that most of the events of the war - up to and including the Nega-Bomb's detonation - have been manipulated and engineered by the Supreme Intelligence to jumpstart the Kree's stagnant evolution.
Horrified by this revelation, and faced with the problem of what to do now with the captured Supreme Intelligence, a group of Avengers decides that the Supreme Intelligence should be killed for its act of genocide.
Aftermath of the war
The immediate aftermath of the storyline is explored in the Captain America and Quasar titles. Captain America #401 (June 1992) examines the effects of the conflict on Captain America, including his disappointment in teammates who disobeyed his orders and in the Avengers group as a whole.
Quasar #35 and #36 (June - July 1992) explore the larger repercussions of the storyline, including the impact on the wider cosmos of the Nega-Bomb explosion, the sudden demise of billions of lifeforms, and the collapse of a major space empire.
Other comics which tie directly into the events of "Operation Galactic Storm" include Silver Surfer (vol. 2) #79 (April 1993) which features the return of two Kree characters, Doctor Minerva and Captain Atlas, who are thought to have died after "Operation: Galactic Storm"; and X-Men Unlimited #5 (June 1994) which features the Shi'ar's formal ceremonies of the annexation of the Kree Empire into the Shi'ar empire, likewise Avengers Forever #8 (July 1997), features how the events of the crossover may lead (and led at least in one timeline) the Avengers to become a paramilitary group that controls a vast and repressive interstellar empire, Iron Man's actions at the time having been provoked by Immortus to create a crucial schism in the team that would prevent them from following this path.
Sequels
In a more general sense, the implications and repercussions of the events depicted in the crossover have had a wide and ongoing impact on many stories set in the Marvel Universe, most especially those featuring the Kree, Shi'ar, and Skrull, as the events of the crossover altered the status quo of each of these races to varying degrees.
Many subsequent Avengers storylines feature attempts by surviving Kree to exact revenge on the Avengers team for their supposed role in the Nega-Bomb's detonation, more specifically Avengers #364-366 and the 1998 four-part Avengers crossover Live Kree or Die!.[2] The former introduces Deathcry to the Avengers, a Shi'ar rebel who is part of a secret movement seeking to aid the Kree suffering under Shi'ar rule. Deathcry would ultimately leave the Avengers in Avengers #389 to help fight alongside the Kree.
The crossover events "Avengers Forever" and "Maximum Security" restore the Kree Empire to its former glory. Using the Time Crystal acquired in "Avengers Forever," the Supreme Intelligence evolves the Kree into a new monstrous form known as the Ruul. Pretending to be a newly discovered species, the Ruul manipulate the Galactic Council, a coalition of the universe's oldest planetary ruling powers, into turning Earth into a prison planet for alien criminals and attempt to weaponize Ego the Living Planet. However, Earth's heroes liberate Earth and free it from Ego.
