intelligence activities concerned with identifying and counteracting the threat to security posed by hostile intelligence organizations or by individuals engaged in espionage or sabotage or subversion or terrorism
`Johnny' was applied as a nickname for Confederate soldiers by the Federal soldiers in the American Civil War; `greyback' derived from their grey Confederate uniforms
used by Northerners of Confederate soldiers; "the rebel yell"
take part in a rebellion; renounce a former allegiance