"Significant contributions" does not make one group the race that has done something.

Only "nobody else made significant contributions" makes one group the race.

I grant that articles are annoying; many languages don't have them. But English does. And when you say the race, you are very clearly and unambiguously stating that no other race made a significant contribution. That's what the definite article signifies: there is no other; this is it. So, if you just were misunderstanding what you said, maybe you want to fix your comment, and if so I'll remove mine.

As you ought to be able to tell (at least now that we're clear on what "the" means) from the content of my comment, I do not deny in the least that African Americans contributed greatly. I only deny that it was exclusively they who contributed to the development and defense of the U.S., because that is badly wrong.