You really have to admire anyone who decides to make a hero of themselves. It must take a considerable effort to decide to put superpowers to good use for the benefit of humanity, when you're faced at every turn with the haunting reminder that using them for evil would make life a hell of a lot easier very quickly. The pay-off is obviously appealing, since adulation is the greatest currency in the known universe - even if it's no help in putting food on the table - and as humans, we're always holding out for a hero, as the great philosopher Bonnie Tyler so succinctly put it.
Sometimes, that heroism rubs off and normal people are compelled to stick their necks out to make a stand, and to make a name for themselves, like the lone German man standing up to Loki or that man who went out shopping and ended up stopping an advancing column of tanks. These people deserve to be adored, and showered with appreciation from a great height, because their actions and their sacrifices had a positive impact on the world.
But then there are those who stride out as heroes to absolutely no benefit at all; jumping on grenades that were never going to explode anyway, or even worse laying down their lives when the battle is already won, or without any effect whatsoever. They might be still heralded as heroic, but that doesn't hide the fact that they were also largely useless, and their great acts of heroism were entirely redundant.
To celebrate these unfortunately pointless heroes, we're looking at the examples from Hollywood history of characters who valiantly made sacrifices for a world that just went on spinning exactly the same way anyway.
Tony Stark - The Avengers
It would be churlish to suggest that Tony Stark's self-sacrifice to save the world from the Chitauri, by ramming a nuclear weapon up their universe's tail-pile, but the tone of the sequence is played as a misdirection that is supposed to mean as much to Stark's character arc as to the fate of New York.
Throughout his arc in the MCU, Tony has been presented as conceited and self-centred, and ultimately as an inferior leader because he wouldn't dive on a grenade to save his team - with the implication being that Captain America would, much to Iron Man's chagrin - so when he chooses to sacrifice himself to save everyone, he's getting the right full-stop to that narrative arc.
He even tries to say goodbye to Pepper in a particularly emotional sequence, but it ultimately means nothing, because in not allowing Tony to kill himself, Marvel robbed him of the follow-through on his epiphany, and he largely does back to being the same old Tony (with a few war wounds) in Iron Man 3 - impulsive, arrogant and self-serving.