The first Black officer to graduate from West Point was 2nd Lt. Henry Ossian Flipper in 1877. A signifiant senior officer in the US military was an Air Force General - General Daniel "Chappie" James, Jr. who learned to fly at the Tuskegeee Institute and graduated in 1942. He was a man of significant reputation and every tribute is deserved.
In 1977 Clifford Alexander was made Secretary of the Army during the Carter administration and he had significant political experience prior to that. He was the first African American to hold the position of Student Body President when he attended Harvard.
Others include General Benjamin O. Davis, Jr., General Colin Powell, General Johnnie E. Wilson, General William Ward.
The following names are taken from the website below under African American Military Leaders:
Four Star General Edward A. Rice Jr.
Four Star General Lloyd W. Newton
Four Star General Daniel James Jr.
Four Star General Benjamin Davis
Captain Joseph N. Peterson (Thunderbirds)
Major Robert H. Lawrence, Jr. (astronaut, test pilot
Major General James F. Hamlet
Brigadier General Roscoe C. Cartwright
Captain Ronald A. Radcliffe
Major General Charles F. Bolden, Jr.
Major General Clifford L. Stanley
Major General Leo V. Williams, III
Major General Arnold Fields
Staff Sergeant Aubrey L. McDade, Jr
Captain Donnie L. Cochran (Blue Angels)
Admiral J. Paul Reason
Rear Admiral Barry C. Black
Rear Admiral Osie V. Combs
Vice-Admiral Ed Moore
Rear Admiral David L. Brewer III
Vice Admiral Samuel Gravely, Jr.
Rear Admiral Lillian Fishburne
Rear Admiral Erroll M. Brown
My point is, while there have been fewer African American senior officers, that does not diminish those who have gone before and created the standard that should be upheld - and did so under much more difficult circumstances. I was unable to find a table that reflected current diversity and if you could oblige, I can comment further. Suffice to say that there have been and are, fine men and women of African American descent in the officer cadre of the US military and they are the standard that others should aspire to. WE should not forget those African Americans who became astronauts - Col. Guion Bluford - the first African American in space, followed by: Col. Frederick Gregory, Major General Charles Bolden (now Director of NASA), Dr. Bernard Harris, Jr., Dr. Mae Jemison, Captain Winston Scott, Lt. Cdr. Robert Curbeam, Dr. Yvonne Cagle, Major Michael P. Anderson, Ms. Joan Higginbotham, Dr. Ronald McNair, Dr. Stephanie Wilson (MD), Col. Benjamin Drew, Leland Melvin (Msc), Major Robert Lawrence, Robert Satcher, Jr. and finally, Lt. Col. Merryl Tengesdal - the first and only female African American to pilot a U-2.