Every so often, Senator Marco Rubio gives what is invariably billed as a "major" speech on U.S. foreign policy, where he invokes Ronald Reagan, calls for an increase in military spending, inveighs against isolationism, and flattens history to suit his purposes. If there are lessons to be learned from the Vietnam War, the arming of the mujahideen in Afghanistan, or the 2003 invasion of Iraq, don't look to the Florida Republican. He has no use for events that suggest the limits of military power, the danger of unintended consequences, or the staggering cost of wars gone wrong. He draws only from events that he regards as bolstering the case for a bigger war machine that is deployed more aggressively all over the world.

History offers some moments when hawks were vindicated. But to be a credible candidate for the White House, a politician should have to show that he or she understands it isn't always 1939; that declaring an adversary an "Evil Empire" doesn't always presage its collapse; that U.S. power can't always be as unrivaled as in the immediate aftermath of the Cold War. Republicans especially ought to be judged in part on whether they understand the Bush administration's foreign-policy mistakes. Rubio fails all of these tests. This is illustrated by stances he takes, like his 2010 declaration that America is better off for having invaded Iraq in 2003. But it's also evidenced by his general approach to U.S. history. He seldom if ever invokes the past as something that should complicate our understanding of the present. For Rubio, the past only confirms his ideological instincts.

Consider his most recent "major" foreign-policy speech, delivered last week in Washington, D.C. "There have always been those who argue that America shouldn’t concern herself with the affairs of the world—that what happens an ocean away bears little relevance to our people," he says early in the speech. "Thankfully, there have also always been those who ... argue that foreign policy is domestic policy, that our people’s interests and safety require defense capabilities so robust that they deter aggression and violence before they take hold ..."

That is one part of Rubio's ideology: America should spend so much on its military that no one ever messes with us. Isolationism will lead to more wars in the end. Most Americans believe that to a degree. I believe, for example, that we ought to spend more on our military than any other country. But for Rubio, spending more on military expenditures than all of our rivals combined still isn't enough.

Here's an example of how Rubio invokes history in dubious service of his ideology:

George Washington was one such leader. When he delivered the first ever State of the Union address, he asserted the need for American strength. “To be prepared for war,” he said, “is one of the most effectual means of preserving peace.” But many in Congress disagreed. They assumed our hard-won independence meant the threats of the Old World had finally become irrelevant—that domestic issues could at last occupy our full focus. So against Washington’s wishes, they cut our Navy’s funding, leading it to be decommissioned.

The consequence of this move was devastating, and the lesson it taught our nation still applies today. At that time, America’s economy relied heavily on trade with Europe. But without a navy, our merchant vessels fell easy prey to a force of thievery and terror known as the Barbary pirates. Off the coasts of Africa and Europe, they attacked, killed, and enslaved our sailors. They plundered our ships and demanded exorbitant bribes, dealing a blow to our economy at home. But there was nothing we could do. America was defenseless.

If Rubio were taking World History 101, his professor might call him into office hours to make sure he understands that the Barbary pirates (who were state-sponsored actors, by the way) did not note cuts in U.S. naval funding and take up piracy. They'd been seizing ships and taking slaves for at least two centuries at that point. Their fleets were the scourge of most seafaring European nations at one time or another. Countries with naval fleets far more powerful and proximate than anything the United States could've mustered in 1789 were paying tribute to multiple North African countries to protect their merchant ships.

The Revolutionary War guaranteed that U.S. merchant ships would no longer enjoy the protection of the British Navy. The treaty concluding the Revolutionary War kicked off a period in which the U.S. had less protection from its ally France. Those events, much more than cuts to naval funding, led to increased troubles with piracy on faraway seas. Even before postwar cuts, the Navy of those years was in no shape to defeat pirates in North Africa.

Rubio speaks as if the Congress of that era irrationally believed America to be unaffected by the rest of the world and let the Navy lapse for that reason. In fact, the earliest U.S. Congresses understood that America was in a perilous financial condition, that excessive expenditures could cause European powers to withdraw credit, that there were obvious limits on how far the fledgling country could project force, and that apart from financial constraints, a major naval fleet could cause the U.S. to be embroiled in intra-European wars that would better be avoided.

It would be one thing if Rubio noted these complicated considerations and made the case that the U.S. should've built a bigger navy in 1789 or 1792 anyway. But he's seemingly unaware that factors other than ideological isolationism were at play, so much so that he blithely presumes naive idiocy on the part of the first Congress. It's as if he presumes they made decisions about foreign policy as ideologically as he does. He can't conceive of the fact that the U.S. might've had bigger concerns in its very earliest years than immediately mounting a force to tame Tripoli.

Rubio goes on:

Even after we re-commissioned our Navy and dispatched it across the Atlantic, it took two Barbary Wars and nearly 15 years to prove American strength and secure safe passage for our ships. America was dealt a hard lesson through this affair: we must be prepared for threats wherever they arise, because our nation is never isolated from the world. Tremors in global affairs can fracture the foundations of our domestic economy.

Why did it take "nearly 15 years" to secure safe passage for our ships from the Barbary pirates? In large part because in between wars against the piratical states of North Africa, the U.S. fought another war against Britain, which was capturing American sailors at rates that were orders of magnitude higher than those inflicted by any other naval force.

The Barbary pirates were a tertiary concern, what with the British naval blockade of the entire East Coast, the British invasion of the U.S., and the burning of the White House. U.S. forces were also fighting Native Americans on the frontier.

All things considered, the attempts of early Congresses to muddle through the conflict with the Barbary pirates proved successful precisely because of America's nimbleness. Early on, when the United States was broke and weak, it made sense for President Washington to deploy his secretary of state, Thomas Jefferson, to try to buy off North African states. In time, as America grew stronger, using force to secure safe passage for merchant ships became the better option. That changed during the War of 1812, when there were more pressing concerns, and changed again after that conflict. The U.S. was stronger. It could credibly attack North African navies.

Rubio's look back at the Barbary pirates suffers from the same flaw as his analysis of contemporary foreign policy. He looks at every problem in isolation, as if priorities, available resources, and what can be realistically accomplished are irrelevant.

What Rubio regards as "moral clarity" and consistency in ideology are far more important to him than analytic rigor, strategic flexibility, or empirical results. The last of these failings is most clearly illustrated by Rubio's gloss on terrorism. "During what many referred to as a 'procurement holiday' under the Clinton administration, we both shrank the size of our armed forces and shifted away from modernizing our inventory," he said. "This happened just as emerging technologies were revolutionizing weapons capabilities around the world. The result was that we failed to be prepared for the challenge that revealed itself on 9/11."

This is not a good example for Rubio.

His notion that America will be safe from attack if only it maintains a large enough military cannot account for suicide missions undertaken by non-state actors. And it's hard to see how more procurement during the Clinton years would've transformed the wars in Afghanistan or Iraq into successes. Rubio's speeches are taken by many as an attempt to prove that, if elected president, he'd be a capable steward of foreign policy. But they always suggest the opposite conclusion to me. He'd be an ideologue with "moral clarity" born of oversimplification.

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