I finally got around to reading Marvel’s Siege and realized something: even though they set in motion the destruction of Chicago’s Soldier Field and the subsequent casualties, Norman Osborn and Loki were trying to be heroes.
Unfortunately for them, they go about it the wrong way.
The goal of the Soldier Field incident was to spark a war between the United States and Asgard, giving a chance for them to be seen as heroes by their respective people, which would finally give them a chance to ascend to power legitimately. Norman would shed the image of being the sociopath Green Goblin and overcome that stigma by forcing Asgard out of the United States. Loki, always seen by the Asgardians as being a power-hungry, manipulative trickster, would be seen as a great hero by protecting kingdom. These acts of heroism would allow Norman to be the President of the United States and Loki could take the throne of Asgard, finally fulfilling their quests for power.
There plan is flawed, and soon their diabolical plan is exposed. Norman is captured as a war criminal, pretty much ruining any chance of him being perceived as being a brave and noble hero.
Thanks to their arrogance, Loki suffers a much worse fate. Norman lost control over the insane minded and insanely powerful Sentry who winds up killing Loki. But before Loki dies, he shows a character trait that separates him from Norman. Loki has the potential for good. Realizing that he himself is the sole reason for the destruction of his beloved Asgard, he arms the Avengers with the enchanted norn stones that give them a fighting chance in stopping the out of control Sentry.
Their actions in Siege shape how the characters will be regarded in the future. Norman is still insanely power-hungry, blaming his failures on a re-emergent Green Goblin persona and is plotting a new way to take over the world. Loki, after showing noble and selfless acts in an attempt to save Asgard, has been reincarnated as a child and is given a second chance to redeem himself for his past transgressions.