They meant the state militias, which were "regulated" somewhat by Congress. Congress was given that power In Article 1, section 8 of the Constitution which says "To provide for organizing, arming, and disciplining, the Militia, and for governing such Part of them as may be employed in the Service of the United States, reserving to the States respectively, the Appointment of the Officers, and the Authority of training the Militia according to the discipline prescribed by Congress" So it would seem to me that the states lost much control over the militias with the crafting of the Constitution. Which is why, and I emphasize this, the 2nd amendment was established in the Bill of Rights, for the right of the people to bear arms, regardless of what control the federal government had over the militias. In my opinion, the 2nd amendment makes more sense, seen from this perspective.