User blog comment:Mejiaj1/Luffy wants to defeat all the Yonkou? My thoughts about it/@comment-25485316-20130124052056

Luffy continues to get stronger as the story moves on. So far, since the timeskip, we've only seen him fight weaklings (Hody, Caesar). Sure, Caesar beat him with a few tricks, but in reality, he was way stronger than both of them.

Luffy grew fast during the first half of the series. Over the span of a few months, he grew from having difficulties against Don Krieg and Buggy, to completely kicking the asses of two warlords (people probabl y thought they were invincible back then too.)

They aren't going straight into a battle. There will probably be a few arcs before that continue to make the Straw Hats grow, and Luffy will at least be able to put up a fight.