Then why didn't the 2nd half of the Amendment say "...the right of that portion of the People enrolled in the Militia to keep and bear arms, shall not be infringed." ???????
The words "the People" have been interpreted in MANY Supreme Court cases to mean all of the people, or at least all of those who are subject to US law. To rule that the 2nd only applies to adult white male citizens is utterly absurd on its face, and would turn decades of precedent on its head. It ain't happening. Other things might, but this twisted idiocy won't.
Space concerns? They could have.
Why doesn't Article I, Section 2 of the U.S.Constitution read, "The House of Representatives shall be composed of members chosen every second year by that portion of the people of the several states who are allowed by those states to vote, and the electors in each state shall have the qualifications requisite for electors of the most numerous branch of the state legislature"?