From AMERICAN SPHINX The Character of Thomas Jefferson by Joseph J. Ellis

"Several Muslim countries along the North African coast had established the tradition of plundering the ships of European and American merchants in the western Mediterranean and eastern Atlantic, capturing the crews and then demanding ransom from the respective governments for their release. In a joint message to their superiors in Congress, Adams and Jefferson described the audacity of these terrorist attacks, pirates leaping onto defenseless ships with daggers clenched in their teeth. They had asked the ambassador from Tripoli, Adams and Jefferson explained, on what grounds these outrageous acts of unbridled savagery could be justified: "The Ambassador answered us that it was founded on the laws of the prophet, that it was written in their Koran, that all nations who should not have acknowledged their [Islam's] authority were sinners, that it was their right and duty to make war upon them wherever they could be found, and to make slaves of all they could take as prisoners...."

This event occurred between 1784-1789 while Jefferson was ambassador to France and Adams (2nd president) was ambassador to England.

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