In March Clapper stated he would specifically have known if a FISA warrant was issued against any Trump campaign officials. Last night Clapper stated he held no knowledge of the FISA warrant. Clapper is walking through a legal minefield.
He would know if US Intelligence officials sought a FISA warrant. The FBI is a law enforcement agency and has nothing to do with Clapper.
The question that should be asked is if "you would be aware of a FISA warrant sought by the FBI".