In the first issue a school was blown up, and the New Warriors were blamed, generating massive popular outrage. This outrage extended to all superheroes, not just to the New Warriors. To show the shift in public opinion, a later scene shows a mob attacking the Human Torch in line for a movie, and leaving him unconscious in the street. During that part, someone asked the Human Torch if he has burned a school. In context, it's a mob mis-blaming him for the New Warriors incident, and the lack of further clarifications seem to confirm it. But in fact, the Human Torch did burn a school some time ago. It was in the nineties, during Tom De Falco's run on the Fantastic Four. He had enrolled at the Empire State university, and he was attacked by Paibok (a Super-Skrull), Devos (an alien with a battle armour) and Lyja (a Skrull who can fire laser beams from her hands). And, as he had a "I'm a tough guy" day, he did not call for help, but attempted to defeat them all by himself. They overwhelmed him... so he made a nova blast. The enemies escaped, but the whole campus was set on fire, because of his arrogance in not calling for help when he had to. At the time, this had no long-term effects but it does cast a different light on the mob scene and the Civil War in general.
In the Secret Wars version, the cause of the explosion is confusing. Black Panther tells Dagger that Stark initiated the self-destruct explosion, planning to leave somehow and leave the others trapped. Then, Hill tells Stark that the Black Panther hacked that system to activate it, so that the unregistered heroes leave in one of Cloak's portals and leave the pro-reg heroes in the explosion. Perhaps he simply lied to Dagger about his true plan. Or perhaps... that scene was narrated by Miriam Sharpe, a mere civil, who was not there and did not witness any of this. How does she know this? Simple: because both leaders had to explain the events later to the population of their own countries. And each one wrote history as they saw fit. The Iron propaganda is that the Black Panther hacked the self-destruct explosion and tried to trap the registered heroes in it: Iron Man is not guilty. The Blue propaganda is that it was Iron Man who activated it, trying to trap the unregistered heroes: Captain America is not guilty. Sharpe simply read about both versions of the events, and tried to come up with a middle-ground version that reconciles both of them.
It makes perfect sense that Spider-Man would join the pro-registration side (at least initially, before watching the things being done to advance it). Force superheroes to be responsible in the use of their powers? Why wouldn't he support it? After all, that's his life motto from day 1: "With great power Comes Great Responsibility". Also, unmasking on a live press conference may have not been a good idea, but it was not out of character. Making huge mistakes and then whangst over them is something that Spider-Man does all the time, also since day 1.
The Civil War event is often criticized for its heavy Depending on the Writer portrayal of the SHRA, often veering into Armed with Canon at times. Pro-reg writers portray the act as a positive way to end the constant Hero with Bad Publicity conflict that dogs all but a few heroes by giving them explicit government approval along with some guidelines to follow to keep it. Anti-reg writers portray the act as a forcible draft that's little more than an excuse to eliminate almost all heroes while whipping the pro-reg heroes into government slaves. However, this is actually quite in line with real life, as the vast majority of laws are passed with good intentions, but many different people can and will see them either as a way to helpfully compromise and make society better or as a means to exploit and/or persecute whoever they apply to, and that goes for both civilians and government officials. Civil War, Debate and Switch in the aftermath aside, can be read as a giant deconstruction of the idea of Super Registration Acts, showing how many different people in both the hero community and government react in both positive and negative ways as opposed to the government being unilateral villains and supers being unilateral heroes.
Villains taking advantage of the situation of the Civil War and let's not even get started if the Annihilation Wave decided to set their sights on Earth while the heroes are hamstrung by red tape and bureaucratic grandstanding.
The What If? story What If The Annihilation Wave Reached Earth? shows that due to Drax the Destroyer being unable to revive Galactus, The Annihilation Wave does continue its march taking out several characters (such as the Super-Skrull) and hits Earth during the final battle of the Civil War. Nova is, of course, shocked that the heroes are fighting each other over secret identities when a massive threat is coming and after the situation is explained, the Pro-Reg and Secret Avengers agree on a truce and team up with others such as Doctor Doom to stop the Annihilation Wave. The whole thing ends with Iron Man, Captain America and Nova sacrificing themselves to get rid of Annihilus and his Wave for good.
The Secret Wars version has each episode start with a description of both countries. And we read "President Tony Stark" on one side, and "General Steve Rogers" on the other. The use of "general" instead of "president" may suggest that he is actually a military dictator (a benevolent dictator, perhaps, but a dictator nonetheless).
