In 1967 he took a leave of absence from Cornell to assume directorship of the nascent National Accelerator Laboratory at Batavia, Illinois, which was to be the largest particle accelerator constructed until then (it was to remain so until the beginning of operation of the Large Electron-Positron Collider at CERN in 1989). In 1969, Wilson was called to justify the multimillion-dollar machine to the Congressional Joint Committee on Atomic Energy. Bucking the trend of the day, Wilson emphasized it had nothing at all to do with national security, rather: