They’re not - militias would be formed and controlled by their state government - they’re just a bunch of guys who who started a gang. No state control or sanction. The Michigan Militia is the Michigan National Guard.
They’re the Michigan Militia in the same sense that the Gambino Family was the New York Mafia.
And there absolutely was a standing military in the Constitution- the Navy explicitly.
The limit on Armies was they would need to have funds reappropriated every two years- nothing prevents that from being a standing army - they just have to renew its funding on that timeframe.
Then those same Founders clarified in legislation that a standing army was authorized. Just a small one - and with a requirement that it get refunded every two years. And that legislation could change its character.
“ As the First Congress entered its final day on September 29, 1789, now-President Washington insisted that the lawmakers pass an Act clarifying the Army’s role under the new Constitution.
Back on August 7, President Washington wrote to Congress to remind them that legislation was needed to replace the outdated part of the Articles that pertained to the military.
“I am particularly anxious it should receive an early attention as circumstances will admit; because it is now in our power to avail ourselves of the military knowledge disseminated throughout the several States by means of the many well instructed Officers and soldiers of the late Army; a resource which is daily diminishing by deaths and other causes,” Washington wrote.
Despite a personal appeal from Secretary of War Henry Knox, Congress didn’t act. Washington had to write a second time to the lawmakers, who finally made it the first order of business on the final day of its first session.
Congress finally passed an Act for “Establishment of the Troops,” which also allowed for the President to call up state militias under some circumstances. It also required a loyalty oath to the Constitution by anyone in service.
At the time, the standing federal Army had about 800 members, including officers.”
https://constitutioncenter.orgblog/on-this-day-congress-officially-creates-the-u-s-army