I spent 32 years working for Uncle Sam, in both military and civilian capacities, including command and supervisory roles, so I can state categorically that there is no professional stigma in the Federal service attached to "southern leanings." A large number of Federal employees are members of the Sons of Confederate Veterans and the Military Order of the Stars and Bars. Many of the larger agencies and installations have active Civil War Roundtables, where pro-Confederate presentations are often made. Many Federal employees have written books and articles with a decidedly pro-Southern theme. There are a great many Civil War reenactors who portray Confederate soldiers, who are in the Federal service.

Overt racism certainly has adverse consequences, but there is nothing exclusively Southern about racism.

Whatever other fears you may have about going public are best known to you, but retaliation on the job in the Federal service is not a legitimate concern. If you have some anecdotal example of such retaliation, you can bet that there something else involved.