"I don't want to conquer anything, the Pirate King is the one with the most freedom!"
As a child, Luffy had called out to Shanks that he, Luffy, would become King of the Pirates. A childish whim, the belief and hope of surpassing others and becoming stronger. That's all it was at first. Becoming stronger than Shanks, going on an adventure. The weight of those words claiming his 'dream' were not heavy. Not yet.
Luffy knew all the Strawhat's dreams and the reasons behind them. Their personalities, their pasts. In truth, the crew knew nothing about Luffy, only his personality, what they had done together, and that he had a brother. Luffy claimed that the past was the past. He didn't care what happened before, only what's happening now.
Yes, that was part of it. But...Luffy had a larger reason. Maybe he was doing it unconsciously, or maybe he knew. He didn't want to look back at the past, it would only drag him down. Luffy's past was not of an average person, it was painful, and filled with grief. He didn't want anyone to know of his past, not without telling them himself. His crew had painful pasts also, and that didn't make them any less of a person. But Luffy thought different about himself. He didn't want to see pity, pity others had shown his crew mates, he didn't want it directed to him.
He didn't need it, it would just be more baggage. Luffy didn't want the image of him his crew mates saw to change.
Luffy's words of becoming Pirate King first gained weight after Sabo. After his brother. It was loneliness that started it, and Sabo that got it rolling. His desires clashed, and he wasn't certain what he wanted anymore.
What did it really mean to have a dream? To die? To have such a desire that you would accept death if it meant accomplishing it? What did 'Pirate King' even mean? To go on a grand adventure, to prove to everyone he was strong, that's what he wanted, wasn't it? Luffy didn't know anymore. Pirate King was nothing if it meant he was alone.
More weight piled on when Ace left Goa. Luffy smiled and waved, even though, despite his apparent happiness, he was crying inside. He was alone again. Not in the sense that Ace was gone forever, like Sabo, but Luffy was alone. The nights were darker than he remembered, colder too. The monsters and beasts of his dreams were scarier, and he had only the air to talk to. Dadan and the bandits were okay, occasionally, but Luffy missed Ace, and Sabo.
For a while, the term Pirate King was said with scorn. It was a ridiculous dream. What was the point? Why did he want to be Pirate King? Why?
Still, he set out with those words. His 'dream'. Was it a dream? He spoke those words loudly, clearly, with confidence. Luffy seemed so sure of himself. That was the picture he built up for his comrades. Because in the beginning, it was for them. He thought maybe he'd found the reason for his dream, to help his nakama achieve theirs. Eventually it became more. It became his title. He was going to be Pirate King, he was certain. He would be the strongest, someone who could protect his Nakama, he would be so strong, no one would ever be able to touch them.
Then it changed again. Ace was gone. Just like Sabo. Luffy's heart shattered. So did the dream he had cradled. Pirate King? Please. Luffy snorted and cursed his foolishness. He was supposed to become the strongest, to protect his nakama, his brother. His wonderful, beautiful, brother...
What was the point of being strong to protect others if the journey only took them all away?
And again he reconsidered his dream, and its meaning.
It took a long time to fix his heart and mind, and even then, his heart would never be the same, and he knew it. Ace was special. For Ace's life Luffy would have thrown away Pirate King without a second glance, or killed himself.
Sabo, who died for freedom, Ace who died from freedom. Freedom. There was that word, the one that was intertwined with the very origins of Pirates.
Why had his brothers strived for freedom so much?
Freedom.
In the next two years, Luffy realized something. Freedom was the ultimate achievement, it was both his brother's dreams. Pirate King was a title to the person at the top, and the top was the freest. That's when the meaning of his Dream finally fell together.
The meaning of Luffy's dream was freedom. The world's most precious item.
Pirate King, it was a title, one that he would attain.
He would get that freedom. That freedom his brother's wanted. Ace and Sabo were in his heart, his mind, in every decision he made.
Freedom belonged to them, so Luffy would get it for them.
"I'm gonna be King of the Pirates!"