It is about the first sentence “do solemnly swear that I will support and defend the Constitution of the United States against all enemies, foreign and domestic”
Some of us civilians likewise swear that oath. The tough part lies in clearly identifying the domestic enemies. A few are obvious, but most are well-disguised. “By their fruits, ye shall know them.” But civil war is coming. By some reckoning, it has already begun — ask Rep. Scalise.