A professor emeritus at Yale University has died at the age of 89. Donald Kagan was known for his study of ancient Greece and his neo-conservative views on foreign policy.
He argued that much of the carnage of some of history's worst wars could have been avoided, if political leaders had confronted the aggressors earlier.
Kagan started at Yale in 1969. His passing was announced by the university.
Among his extensive writings, Kagan produced a four-volume history of the Peloponnesian War.
He criticized multicultural programs, and pushed for an emphasis on the study of Western civilization.
Kagan was consulted by conservative politicians, and he supported wars in Vietnam and Iraq.
Kagan was awarded the National Medal for the Humanities in 2002.
