Complex sentence: By 1968 the Americans were well aware of the scope and scale of the Cambodian logistical effort, but remained reluctant to overtly violate Cambodia's neutrality since the US still hoped to persuade Sihanouk to come on board against the communists.
Split into simpler sentences: By 1968 the Americans were well aware of the scope and scale of the Cambodian logistical effort, but remained reluctant to overtly violate Cambodia's neutrality. The US still hoped to persuade Sihanouk to come on board against the communists.