In this source the Foreign Secretary is explaining to the Cabinet about
a recent visit to the USA (in late 1965).
While he was there he raised a number of issues, but Vietnam dominated discussions.
Back in February 1965 the USA had begun a bombing campaign called Operation
Rolling Thunder. It was a huge campaign which lasted for years. It devastated
large areas of North Vietnam, and the bombing also hit nearby Laos and Cambodia.
The aim was to put pressure on North Vietnam and disrupt the supplies coming
from North Vietnam to the Viet Cong in South Vietnam.