Shanks relying on his strength is besides the point. Sure, he uses his strength but invariably in order to avoid bigger bloodier conflicts. Sure, he risked a war with kaido but without a doubt had kaido gotten to marineford the conflict would have been much worst. He risked a fight with WB but shanks was perfectly aware of how big a conflict could come out of ace's quest. At marineford I would argue the context was a little bit different. The marines and WB pirates at that point were largely spent. Either force had exactly zero chance of winning against a fully rested yonko crew at the height of its power. There was no real risk to shanks in this scenario, just any force that went against them would be defeated.
And sure, shanks is willing to fight... but it is a fact that shanks has invariably acted to prevent shit storms. It's also possible shanks has changed since the higuma days. It's been a long decade since then....
Shanks is not pacifist. If he were, he wouldn't encourage Luffy to become Pirate King. Someone who knows what being PK means know it means finding One Piece meaning he's not discouraging anyone from what comes with finding One Piece which both Whitebeard and Otohime have told us.
What Shanks is... is someone that doesn't want useless conflict or bloodshed. He went to Whitebeard to stop Ace from going after Blackbeard. He didn't say they shouldn't fight... he just say "
NOW is not the time for them to fight".
He stopped Kaido not just because he could make the conflict at Marineford was. He ultimately went to Marineford because:
- If Whitebeard dies... the seas would become chaotic and erratic.
One huge thing in One Piece is balance. Balance maintains relative peace. More so, Blackbeard's involvement spelt bad news given that he's ambitious, Shanks knew this. He just didn't want Blackbeard to rise to power and he wanted the younger generation (Ace/Luffy) to grow under less chaotic situations. He's also aware that Ace was the son of Roger.
If Shanks simply wanted to stop chaos, he'd be in Wano on hearing that Big Mom and Kaido were making an alliance.
Shanks ultimately wanted to maintain peace not just for the sake of it:
- But also because he probably knew if Ace went to Marineford... Luffy would also go. He knew Ace was Luffy's brother and he knew that Luffy was the kind to save people he loves. He wanted to save his life or rather... ensure he lives long enough to fulfil his ambition.
Ultimately, Shanks wants Luffy to become Pirate King.
All Shanks is really doing is not stopping conflict for the sake of it, he's trying to prevent it probably because it's not beneficial to his agenda.
Shanks appears like he's a pacifist or at least, we know he's a sensible person who doesn't fight for no reason which is why the WG respect him and accept his audience. In fact, they believe he's not interested in One Piece, so more reason to allow him such privileges.
Shanks wants peace only until the appointed time; WG want peace to ensure they stay in Power until now that they have a power to counter the Emperors and abolish the Shichibukai system. They appear to have mutual goals, but they have different reasons behind peace.
Here is my idea: Shanks will try to stop luffy from reaching OP. Not to claim it himself but rather because of what the consequences of reaching OP are.
The Novel also makes it clear Luffy's returning the hat after he becomes Pirate King. Luffy's still going to have to fight him and defeat him meaning Luffy and Shanks will meet twice at least. Once on his way to fulfil the goal of finding One Piece, and once more after he's found One Piece which will make him PK.
I wouldn't be surprised if Shanks and all the allies he's accumulated assists Luffy in taking down the WG after Luffy becomes Pirate King for the final war.
Shanks however is not a guy just looking to stop wars, he's definitely no pacifist especially having a bounty of 4 billion.