The 15th Constitutional Amendment states, "The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of race, color, or previous condition of servitude." The 19th Constitutional Amendment states, "The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of sex."

The 26th Constitutional Amendment states, "The right of citizens of the United States, who are 18 years of age or older, to vote, shall not be denied or abridged by the United States or any state on account of age."

The addition of these amendments to the U. S. Constitution shows that, most likely

the original authors of the U. S. Constitution did not care about the rights of different groups of people
as times have changed, new groups of people have received the right to vote
different groups of people have no chance of being protected
the U. S. Constitution is outdated and needs to be rewritten because there are so many different groups