 Without collaborators, a U.S. invasion against an army united with the people would have been difficult and costly in lives; in an optimistic estimate, the Pentagon believed that at least two full U.S. divisions were required to overcome the extensive armament the Dominican Republic had acquired as protection against a Haitian invasion.At the end of the Eisenhower administration, a campaign was initiated to deny Cheddi Jagan power in an independent Guyana.This campaign was intensified and became something of an obsession of John F. Kennedy, because he feared a "second Cuba".