Exactly 237 years ago today, on March 28, 1786, two of America’s founding fathers documented the United States’ first exposure to Islamic jihad in a fascinating letter to Congress.

A Diplomatic Exchange in Response to Inexplicable Animosity

One year earlier, in 1785, Muslim pirates from North Africa, or “Barbary,” had captured two American ships, the Maria and Dauphin, and enslaved their crews. In an effort to ransom its enslaved crew and establish peaceful relations, Thomas Jefferson and John Adams — then ambassadors to France and England respectively — met with Tripoli’s ambassador to Britain, Abdul Rahman Adja. Following this diplomatic exchange, the Americans laid out the source of Barbary’s hitherto inexplicable animosity in a letter to Congress:

We took the liberty to make some inquiries concerning the grounds of their [Barbary’s] pretentions to make war upon nations who had done them no injury, and observed that we considered all mankind as our friends who had done us no wrong, nor had given us any provocation.

The ambassador answered us that it was founded on the laws of their Prophet, that it was written in their Koran, that all nations who should not have acknowledged their 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, and that every Musselman who should be slain in battle was sure to go to Paradise [dated March 28, 1786].

Abdul had continued by smugly noting that Islam’s “law” offers “as an incentive” more slaves to those who are first to board infidel vessels, and that the power and appearance of the seaborne jihadis — who reportedly always carried three knives, one in each hand and another in their mouths — “so terrified their enemies that very few ever stood against them.”

One can only imagine what the American ambassadors — who years earlier had asserted that all men were “endowed by their Creator with certain inalienable rights” — thought of their Muslim counterpart’s answer. Suffice to say, because the ransom demanded was over 15 times greater than what Congress had approved, little came of the meeting.

Christian “Infidels” Suffered Beyond Expression

Centuries before preying on the newborn American nation’s vessels, the Barbary States of Muslim North Africa — specifically Tripoli, Algiers, Tunis — had been thriving on the slave trade of Christians abducted from virtually every corner of coastal Europe — going as far as Britain, Ireland, Denmark, and Iceland. These raids were so successful that, “between 1530 and 1780 there were almost certainly a million and quite possibly as many as a million and a quarter white, European Christians enslaved by the Muslims of the Barbary Coast,” to quote historian Robert Davis.

The treatment of these European slaves was exacerbated by the fact that they were Christian “infidels.” As Robert Playfair (b.1828), who served for years as a consul in Barbary, explained, “In almost every case they [European slaves] were hated on account of their religion.” Three centuries earlier, John Foxe (b.1516) had written in his Book of Martyrs that, “In no part of the globe are Christians so hated, or treated with such severity, as at Algiers.”

The punishments these European slaves received for real or imagined offenses beggared description: “If they speak against Mahomet [blasphemy], they must become Mahometans, or be impaled alive,” continued Foxe. “If they profess Christianity again, after having changed to the Mahometan persuasion, they are roasted alive [as apostates], or thrown from the city walls, and caught upon large sharp hooks, on which they hang till they expire.”

As such, when Captain O’Brien of the Dauphin wrote to Jefferson saying that “our sufferings are beyond our expression or your conception,” he was clearly not exaggerating.

The Perpetual, Existential Nature of Islamic Hostility

Back in Congress, some agreed with Jefferson that “it will be more easy to raise ships and men to fight these pirates into reason, than money to bribe them.” General George Washington asked: “In such an enlightened, in such a liberal age, how is it possible that the great maritime powers of Europe should submit to pay an annual tribute to the little piratical States of Barbary? … Would to Heaven we had a navy able to reform those enemies to mankind, or crush them into nonexistence.”

But the majority of Congress agreed with John Adams: “We ought not to fight them at all unless we determine to fight them forever.”

Considering the perpetual, existential nature of Islamic hostility, Adams may have been more right than he knew.

Congress initially decided to emulate the Europeans by placating and paying off the terrorists, though it would take years to raise the demanded ransom. Inevitably, however, hostilities again broke out, leading to the Barbary Wars (1801 to 1805; again in 1815). But by now, the U.S. had built six war vessels.

‘Why Do They Hate Us?’

Thus the United States’ first war — which erupted before it could even elect its first president and intermittently lasted some 30 years — was against Islam; and the latter had initiated hostilities on the same rationale that had been used to initiate hostilities for the preceding 1,200 years.

Though most Americans are now unaware of their nation’s first military conflict, references to it are common. The oldest paean of the U.S. armed forces, “The Marines’ Hymn,” boasts of fighting everywhere for “right and freedom” — including as far as “to the shores of Tripoli.” And the oldest U.S. military monument was made to honor those Americans who fought and died in the Barbary Wars. According to its plaque, “‘Millions for defense, but not one cent for tribute’ became the rallying cry for this war.”

The turbaned heads of the vanquished enemy appear at the foot of the eagle-topped column. Needless to say, although the United States’ oldest monument was for decades located inside the Capitol Building, it now rests in the much less conspicuous faculty club of the Naval Academy in Annapolis.

In short, although the question “Why do they hate us?” became immensely popular after 9/11, it was amply answered during America’s founding, including through a little remembered letter written to Congress 237 years ago today.

Raymond Ibrahim, author of Defenders of the West and Sword and Scimitar is the Distinguished Senior Shillman Fellow at the Gatestone Institute and the Judith Rosen Friedman Fellow at the Middle East Forum.