Oren notes that the stupendous expense of this long series of wars was a partial vindication of John Adams’s warning. However, there are less quantifiable factors to consider. The most obvious is commerce. American trade in the Mediterranean increased enormously in the years after the settlement with Algiers, and America’s ability to extend its trade and project its forces into other areas, such as the Caribbean and South America, was greatly enhanced. Then we should attend to what Linda Colley says on the subject of slavery. Campaigns against the seizure of hostages by Muslim powers, and their exploitation as forced labor, fired up many a church congregation in Britain and America and fueled many a press campaign. But even the dullest soul could regard the continued triangular Atlantic slave trade between Africa, England, and the Americas and perceive the double standard at work. Thus, the struggle against Barbary may have helped to force some of the early shoots of abolitionism.

Perhaps above all, though, the Barbary Wars gave Americans an inkling of the fact that they were, and always would be, bound up with global affairs. Providence might have seemed to grant them a haven guarded by two oceans, but if they wanted to be anything more than the Chile of North America—a long littoral ribbon caught between the mountains and the sea—they would have to prepare for a maritime struggle as well as a campaign to redeem the unexplored landmass to their west. The U.S. Navy’s Mediterranean squadron has, in one form or another, been on patrol ever since.

And then, finally, there is principle. It would be simplistic to say that something innate in America made it incompatible with slavery and tyranny. But would it be too much to claim that many Americans saw a radical incompatibility between the Barbary system and their own? And is it not pleasant when the interests of free trade and human emancipation can coincide? I would close with a few staves of Kipling, whose poem “Dane-Geld” is a finer effort than anything managed by Francis Scott Key:

It is always a temptation to an armed and agile nation

To call upon a neighbor and to say:—

“We invaded you last night—we are quite prepared to fight,

Unless you pay us cash to go away.”

And that is called asking for Dane-geld,

And the people who ask it explain

That you’ve only to pay ’em the Dane-geld

And then you’ll get rid of the Dane!

Kipling runs briskly through the stages of humiliation undergone by any power that falls for this appeasement, and concludes:

It is wrong to put temptation in the pathof any nation,

For fear they should succumb and go astray;

So when you are requested to pay up or be molested,

You will find it better policy to say:—

“We never pay any-one Dane-geld,

No matter how trifling the cost;

For the end of that game is oppression and shame,

And the nation that plays it is lost!”

It may be fortunate that the United States had to pass this test, and imbibe this lesson, so early in its life as a nation.

This article originally appeared in City Journal.