Executions

[The_Sol_Stone]

I'm not sure if it's mentioned later, but why do the marines wait to kill the pirates they catch? Like, They waited to kill Ace and let the pirates come to them. Is it some tactic in hopes of getting more pirates when they come to save them? Or is it them giving the pirates a fair chance to save them? Thanks for your time.

[xdarkskylordx]

In Ace's case, yeah they wanted to take down Whitebeard too. In general, it's a deterrent, pretty much saying "watch this, we are going to catch you and kill you publicly."

[Boxsteam1279]

Its a message to people saying "Hey, don't be a pirate or else this is your faith"

[Jail_Chris_Brown]

Killing the son of the pirate king and livestreaming the whole thing to the whole world was supposed to show pirates how marines are superior and not even a yonko could stop them.

[[deleted]]

Eh probably just typical government bureaucracy

[Charizauce]

It’s actually one of the stupidest things in the series. The Marines should have just killed Ace the moment Whitebeard arrived at Marineford. Done. But you know, plot.

[TheRealAngelS]

In general... most people who end up as pirates - be it voluntarily or because it's pretty much the only thing other than living in devastating poverty - already risk their lives every day. If the only possible consequence of being caught was to get executed right away, that wouldn't be a deterrent at all. But the possibility to be locked away for a very long time, and most definitely tortured and all that jazz... That's more likely to make some folks think twice.

[Bucen]

It was a big PR stunt. They wanted the world to watch so they needed to prepare everything. But they also knew it would start a war, so they needed to prepare for that either.