There is a Sarajevo somewhere in Jordan. It lies well outside Amman, somewhere in the hostile terrain to the east or the north. Were the armed ISIS extremists -- who now call themselves representatives of the Islamic State and soldiers of the new caliphate -- to cross this line, the current conflict that engulfs Syria and Iraq would likely explode and grow more complex and costly by quantum degrees. This is not the sort of red line that is the product of an ill-considered, halfhearted burst of presidential bravado. This is the type of red line that triggers historic change and is worth considering as we mark the epoch-making events in Sarajevo that spawned World War I 100 years ago. 

For now, the wars in Syria and Iraq seem almost to be inviting the United States to remain more or less on the sidelines. Once an amorphous mess, it has seemed to take on something of a shape and symmetry. In both countries today, alliances featuring the ruling governments working in collaboration with Iran and Russia are taking on the extremists. With the announcement this weekend of Russian planes and munitions being shipped to the government in Baghdad, the orchestrated bombings last week of ISIS targets by Syrian jets in Iraq, and the active role of Iran and the Islamic Revolutionary Guard Corps in both places, it almost seems like a traditional conflict with two sides vying against one another. 

David Rothkopf
David Rothkopf was a visiting scholar at the Carnegie Endowment as well as the former CEO and editor in chief of the FP Group.
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Further, with Moscow and Tehran willing to take up the fight against ISIS, it might be tempting for Washington to effectively sit this one out. After all, if the United States wants promises of political reform and the Iranians and Russians clearly don't require it to intervene, the Iraqis will be even harder for America to deal with. Intransigent Prime Minister Nouri al-Maliki may simply opt for the support of Tehran and Moscow, as well as a tacit alliance with Syria's Bashar al-Assad, avoiding the hard work of creating a truly representative Iraqi government -- which also happens to be the most self-serving possible choice. Unfortunately, for the world, the route of "letting others fight our battles for us" might be "easier" -- but it's exceptionally dangerous. 

The two wars that have spilled into one another do not represent a simple two-sided conflict. In Syria, not only is the opposition still fragmented, containing extremist groups like Jabhat al-Nusra that are themselves bitter enemies (usually) of ISIS, but it also involves more moderate groups, like the Free Syrian Army. You remember them? That's the collection of rebels the United States has effectively resisted supporting thus far because it was uncertain of their allegiances or trustworthiness. Three years later, of course, now that ISIS has gone from terrorizing northern Syria to marauding across Iraq, the United States has somehow discovered that it is possible to "vet" suitable partners among them and start offering training and aid. The $500 million that Barack Obama has pledged to this effort is a good thing, though it's diminished by its lateness. Meanwhile, in Iraq, it is not just Sunni extremists versus an out-of-touch Shiite regime in Baghdad. There are more moderate Sunnis who don't relish the prospect of living in ISIS's 13th-century self-declared caliphate. And there are the Kurds who seek and deserve independence -- a fact not appreciably advanced by the declaration of support they received over the weekend from Israeli Prime Minister Benjamin Netanyahu, who is not exactly the ally of first resort you want in that neck of the woods. 

Perhaps even more disturbing is the fact that in its current configuration -- and absent a constructive move toward effective political resolutions in Iraq or Syria -- the conflict offers a panoply of unappetizing potential conclusions. It is fine to pit Assad and Maliki plus Iran and Russia against ISIS, except under the following circumstances: Either side wins or, alternatively, there is a draw. 

ISIS winning and establishing control over Iraq, Syria, or a large zone encompassing parts of Iraq and Syria would be a catastrophe that could haunt the region and the world for decades to come. Were Assad and Maliki to triumph with big debts owed to the Iranians, it would not exactly be a formula for regional stability, and it promises further insurrections and abuses to come. The most likely outcome, a draw, doesn't look much better. Northwestern Syria will be a region of nominal governmental control, with the help of sponsors; some portions of Syria and Iraq will get an ISIS caliphate, a hot zone of extremist mayhem that will likely infect much of the region and from which more global terrorist efforts will emanate. Partition-by-default is a formula for unending conflict. 

This frames the problem of staying out or disengaged. The United States might mitigate risk by leaving the messy business of a distant war to others with more skin in the game. And, it has to be admitted, this might work. All parties might deplete themselves, wear each other down, stay focused on fighting each other, and leave U.S. interests more or less intact. But this also raises the chances that the United States may get outcomes over which it has little or no influence -- that may someday (possibly very soon) require of the country much riskier, more dangerous action, whether it wants to be involved or not. 

 This brings us to that red line in Jordan. Go find a map. Now you determine where this red line might be. You might say it is right at the Jordanian border because any breach of the sovereignty of such a valued ally and bastion of moderation in the Middle East would be intolerable. Jordan has been so dependably helpful to the United States and its interests, so constructive in the peace process with Israel, and such a pillar of the moderate and reforming path in the region that even the U.S. Congress, champions of inertness and the black hole of democracy that they have become, would likely demand American intervention. 

None of this is to minimize the Jordanian military's will or ability to defend Jordan. Rest assured the Jordanian military would step up in a way that the Iraqi military has not. But imagine a time in the not-too-distant future when the Islamic State that ISIS seeks to establish or its failed-state doppelgänger has had some time to take root, acquire further assets, and start picking at the Jordanian border, perhaps from Iraq and Syria simultaneously. Without saying such an incursion is even likely, simply consider its consequences. 

Go back to the map. At least, go back to the map such as it is today. It is clearly changing -- as the Atlantic's Jeffrey Goldberg has been predicting would be the case for the better part of the past decade. Amman is 466 miles from ISIS-controlled Fallujah, but only about half that from the border with Iraq. Amman is just over 40 miles from the border with Syria, roughly the same distance it is from Jerusalem. 

Now consider ISIS's assertion that it wishes to incorporate Jordan into its caliphate. How far into Jordan would an ISIS incursion have to go before alarms went off in Washington? How far before Israel felt it must take more aggressive action to defend itself? 

How would such a response be met in the region? What would be the reaction in the Palestinian territories, where at the moment a Third Intifada is the buzzed-about concern of many and where tensions are today especially high due to the discovery of the bodies of the three kidnapped Israeli teens for whom Israel had been frantically searching since June 12? How complicated would this conflict be? Would the United States and Israel actually fight to ensure gains for Iran and Assad? How would their involvement inflame other extremists? How hard would Iran, Syria, or Iraq fight to protect Israel from the threat of ISIS -- especially if having active jihadists near Jerusalem actually solidified the global tolerance for defective regimes like those in Damascus and Baghdad? It is a situation in which duplicity among tacit allies might be more damaging than the onslaught of avowed enemies. 

Perhaps Jordan would be a red line too far for the would-be Islamic State. Perhaps with the combined firepower of Jordan, the United States, Persian Gulf allies, and, possibly, Israel, they would be stopped dead in their tracks or destroyed. Certainly, we must hope that would be the case. But what would we be left with in a world in which when one terrorist group is destroyed, multiple others pop up in its place? What would the new map look like? What would the cost be of the battles that took place? 

It is far too late to be playing the blame game; there is plenty to go around. These problems are the combination of multiple failures of judgment, of bad faith, of dark ambitions, and of faltering will -- both regionally and internationally. 

Cascading failures, missteps, and the consequences of conflicting ambitions among leaders, extremists, and frustrated peoples are in fact what made Sarajevo the beginning of one of the most ghastly chapters in world history. In this instance, if we are to avoid a regional analogue of such an escalation into depravity, all those who are the heirs to the calamity of World War I -- the United States, Europe, the Turks, and those from across the roiling region itself -- must remember the lesson of its origins: that passivity and inattentiveness to crises allows them to fester and grow more dangerous. This is not someone else's problem if an easily imagined potential turn could draw in the United States and its allies. This is not someone else's problem if it reignites or exacerbates the global terrorism threat. 

Yes, let Iran, Russia, Assad, and Maliki try to defeat ISIS. If there are ways Washington can conscionably assist with intelligence, drones, air power, or military advisors, it should do it. Yes, the United States should work with partners internationally to squeeze ISIS economically wherever possible. And by all means, the White House must send a clear message that Jordan's border or any sign of hostility toward Amman is a real red line. 

But recognize that of all the possible endgames in this newly urgent war, there is really only one that works for the United States, its allies, and U.S. long-term interests: an effective political solution that gives a real voice to all segments of society and ensures at least peaceful coexistence among sectarian groups and a level playing field for all of them. 

Therefore, it is essential in both Iraq and Syria to support a much more actively moderate opposition -- and work with allies in the region on cultivating and institutionalizing that support. This means more tireless diplomacy such as that effectively led by Secretary of State John Kerry and a willingness to take tough stances. For example, while the Iran nuclear talks have been for very good reasons on a separate track, Washington should make clear that threat of regional instability is one it takes as seriously as the threat of weapons of mass destructions. (As we have seen, getting rid of chemical weapons in Syria, while a good thing, has left the real weapon of mass destruction, Assad, in place and has left raging a conflict that has already killed at least 100 times more people than had the chemical weapons attacks that occurred within it.) Therefore, the administration must make clear that it will not embrace lifting sanctions if the Iranians are not playing a constructive role to find a sustainable political settlement in this spreading and dangerous conflict. 

It won't be easy. The risk of failure is high. The political gains at home are likely to be small. It will require a kind of activist multilateralism and hardball realpolitik that makes for good speeches but is really hard to realize in practice. It will require the active engagement of the president of the United States and his cabinet working with allies in the region, in Europe, and around the world as the country has done on few issues in recent years. But sometimes tough options even with long odds are worth pursuing because the costs of doing nothing or too little are so high. That was the lesson of Sarajevo in 1914. 

This article was orignally published in Foreign Policy.