That's suprising to me, the Mexican American war wasn't all that long ago, you'd think there would be a lingering effect on the country.By 1850 it no longer did. Most militias was is very poor shape... and the active ones where social clubs. And there was no State oversight on if men was actually listed on the rolls and if they had the arms they where suppose to have.
In the south it was s bit better since the militias was need in case of a slave revolt, but still in poor shape.
John Browns raid, got the south started to actually focus on their militias and some started spending some money on equipment... giving them a head start when the war broke out.