Adkins appeared with the earpiece on a nationally televised special for the lighting on Wednesday. Some regard the flag as a racist symbol and criticized Adkins in Twitter postings.
But in a statement released Thursday, the Louisiana native called himself a proud American who objects to any oppression and says the flag represents his Southern heritage.
He noted he's a descendant of Confederate soldiers and says he did not intend offense by wearing it.
Adkins -- on a USO tour in Japan -- also called for the preservation of America's battlefields and an "honest conversation about the country's history."