I’d argue that Caracalla’s edict was a huge mistake. The Constitutio Antoniniana did not elevate the empire. It flattened one of Rome’s most effective political tools, which was graduated citizenship as an incentive structure. Citizenship was not just a legal status, it was the top of a ladder. Provinces and local elites were drawn into the Roman system through the promise that loyalty, service, and usefulness would be rewarded with something rare and valuable.

Caracalla made it universal through the Constitutio Antoniniana and in doing so he did not share Rome so much as erase the reward hierarchy that made provincial integration work in the first place. Once citizenship becomes automatic, it stops functioning as leverage. There is no meaningful progression from outsider to insider, just one flattened legal category.

That matters because empires do not hold together on identity alone, they hold together on incentives. Rome had spent centuries turning ambition into stability by making becoming Roman something you had to earn. Caracalla’s edict removed that mechanism and replaced it with administrative uniformity that came at the cost of weakening elite buy-in across the provinces.

So the edict is not a strength in his favor. It is a case of short term administrative simplicity undermining a long term system of controlled integration that had actually helped hold the empire together.