As we know, Dragon is the "worst criminal".
For the longest time we have assumed that this was simply because he was a revolutionary. But I'm starting to doubt that.
Sabo, Dragon's #2, was only worth 600 mil before reverie
Kuma was worth less than 300 mil
Iva wasn't even placed in impel down level 6
Not saying any of these guys are weak, but the government clearly didn't view them as as big of a threat as the yonko commanders. Jack alone was worth more than Kuma + Sabo. Again, not saying he is stronger than either of them.
But if being a revo didn't get Dragon's subordinates high bounties, then I fail to see why simply being a revolutionary would make Dragon the worst criminal. No imo Dragon must have actually done something that pissed the CD's off so much that they made him the worst criminal.
This explains why Akainu hates Luffy so much for being his son. Its very likely that Dragon's crime, whatever it was, happened around the time where he was a marine.