Jean-Francois Kerre` has nightmares about when Nixon sent him into Cambodia in December 1968. He wants nothing more to do with war.
Therefore, he cannot call an engagement with ISIS a “war”, because that would put him in the same box as Nixon and Henry Kissinger.
Check your calendar, by the way. Nixon was not President anytime during 1968.
LBJ was still President until January 1969.