Obviously, the reason for the WG to have this pact with these notorious pirates is to better control the seas. One of the main reasons for the Warlords to exist, is to scare off rookies that think about becoming a big time pirate, and eventually beat the ones that try anyways. Another reason for this pact to exist, is to strengthen the forces of the marines in times of need. The clearest example of this is the battle at Marineford. Every Warlord was summoned to fight against the forces of Whitebeard, and the WG even threatened to withdraw the title of Warlord if they refused to come. Although the system obviously shows some benefits to the WG, we can’t ignore the fact that this same system has given the WG some major headaches before.
Pirates will always be pirates. That’s a lesson the WG has learned the painful way in both Alabasta and Dressrosa. In both cases, a Warlord was acting like the good-guy towards the citizens of the islands, but in the end, they were the ones responsible for all of the problems. The events on both Islands were a painful matter for the government. In reality, the government that is supposed to protect its people, let an evil maniac run and ruin the country behind the scenes. In both cases the problem was resolved by another pirate crew instead of the government itself. The fact that the government indirectly caused this problem and didn’t even solve it, gives major trust issues towards them and in the end, will result in severe dissatisfaction.
Probably the biggest disaster for the WG regarding the Warlord system is Teach’s betrayal and his break in/out of Impel Down. This is by far the best example of a person joining the ranks of the Warlords for the sole reason of betraying the WG later on. Teach had everything planned out beforehand and used his title to have an easy way into Impel Down (the world’s greatest prison), gather a crew of the most notorious criminals, break out again, and then wreak havoc at the very Marine HQ that the Warlords were supposed to defend. There is no greater backstabbing in the history of the Warlords than this one.
But abolishing the Warlord system would have been a very painful task. They are responsible for tasks that greatly benefit the WG and they exercise a relatively big amount of influence on the seas. Another thing that prevented the WG from cutting ties with Doflamingo, was the fact that he knows about the “national treasure of Mariejois”. The WG was definitely afraid of information about this leaking out.
Now that Doflamingo is locked up, it might be possible for the WG to abolish the system now that it’s “weak”.
One of the things that would change after the abolition of the Warlord system, is the control the WG has on the seas. The amount of rookie pirates that enter the Grand Line would surge. The Warlords would no longer have the task to minimize this group, this means that more people will survive the Grand Line and this news will also convince even more people to attempt the journey. This could lead to more prominent rookie pirates that would rise like the worst generation did before them.
Another result of the abolition would be the fact that the Warlords would become enemies of the Marines again, not even considering the fact that new alliances might emerge between ex-Warlords, maybe even some super rookies, or even a Yonko.
We have to consider that the seas are a dangerous place at the moment. Like Doflamingo stated, there’s a big war coming now that Whitebeard’s era is over. The current Yonko are all power houses and some of them are creating bigger and bigger forces. Kaido is creating a zoan fruit army prepared for war, Big Mom is upgrading her forces with Vinsmoke technology, and Blackbeard is collecting devil fruits for his crew and his ambitions are a danger to the WG too.
Of course the Marines and World Government have a lot of powerhouses for themselves like the Admirals, the CP’s, the Vice Admirals, Vegapunk’s PX army, and old legends like Garp, Sengoku, maybe even Kong. There could even be people that work for the WG that we haven’t even heard of, but the fact remains that abolishing the Warlord system would severely shift the balance of the world in the favour of pirates and possibly even the revolutionary army who could use this opportunity to strike.
by S.