I've talked briefly about this previously in this post where I write that,

It is important, therefore, to consider the aftermath of the assassination of Dr. King in 1968. While there were white soldiers who were equally shocked and saddened by the news coming from the United States, there were also white soldiers who openly celebrated the murder. In Cam Ranh Bay, a Confederate flag was hoisted in celebration and white men donned improvised Klu Klux Klan robes, burned a cross, and paraded around the base. This wouldn't be the first time, James E. Westheider points out, as crosses were burnt in both 1969 and 1970. Furthermore, the Confederate flag was openly displayed by white troops throughout the war, something that African Americans rightly despised. While white soldiers flew the Confederate flag, black symbols (such as the "Black Is Beautiful" poster) were actively suppressed.