Ideally ya. But how would Paradise go about doing that in their short time they had from knowing about the outside worlds intention till the rumbling? Theyre one island against multiple nations who all want them dead and who all are decades if not centuries ahead technologically in certain ways. Also you need willing people. They never really show the common folk having any disagreements or tension with Marleys government. Only the eldians in the ghettos and many of them were pro Marley too. Even if they could instill a revolution with the eldians and with the help of the titans they have I dont see how you topple every countries governments and change the minds of their citizens before they go through with their attack that was a month or two away. They tried with attending that summit thing and pleading a case for peace with the help of the Azumabito family and the entire world told them to fuck off and get ready to die.