In The Federalist No. 43, James Madison explained the need for a "federal district," sub*ject to Congress's exclusive jurisdiction and sep*arate from the territory, and authority, of any single state:
The indispensable necessity of compleat authority at the seat of Government car*ries its own evidence with it. It is a power exercised by every Legislature of the Union, I might say of the world, by virtue of its general supremacy. Without it, not only the public authority might be insult*ed and its proceedings be interrupted, with impunity; but a dependence of the members of the general Government, on the State comprehending the seat of the Government for protection in the exercise of their duty, might bring on the national councils an imputation of awe or influence, equally dishonorable to the Government, and dissatisfactory to the other members of the confederacy.
Madison's concerns about insults to the "public authority" were not speculative. In June 1783, several hundred unpaid and angry Conti*nental soldiers had marched on Philadelphia, menacing Congress in Independence Hall itself. Pennsylvania refused all requests for assistance and, after two days, Congress adjourned. Its Members fled into New Jersey.
The incident made a lasting impression. The Framers referenced it over and again in defend*ing their provision for a "federal town," which Anti-Federalists persisted in visualizing as a sink of corruption and a potential nursery for tyrants. In fact, however, the need for a territo*ry in which the general government exercised full sovereignty, not beholden to any state, was probably inherent in the federal system itself.