On Wednesday, it looked like an old battle in Lebanon and Israel might be reignited. By Thursday, it looked like tensions had declined. In a statement labelled Communiqué No. 1 (implying that there would be others tied to the event), the Lebanese Shiite militant group Hezbollah claimed responsibility for an attack on an Israeli convoy on Wednesday morning, in the Shebaa Farms area, a disputed Israeli-occupied tract of land at the junction of Israel, Syria, and Lebanon. The attack left at least two Israelis dead, and seven wounded. Ensuing clashes between the two sides also killed a U.N. peacekeeper and threatened to blow open a front that had largely been dormant since the devastating war between Hezbollah and Israel in 2006.

Hezbollah said that the ambush was retaliation for an Israeli strike in Syria on January 18th, which killed an Iranian general and six Hezbollah men, including Jihad Mughniyeh, the son of Hezbollah’s revered strategic mastermind, Imad Mughniyeh, who was assassinated in Syria, in 2008, in an attack widely blamed on Israel. If this sounds confusing and circuitous, that’s because it is. The Middle East today is ever more a molten mess of conflicts spreading across borders that increasingly mean little on the ground. Although the Israeli-Arab conflict is as old as Israel itself, history will likely record that it lately has been exacerbated by Syria, the great hemorrhaging wound of the Middle East. It is what Afghanistan was in the eighties, importing and exporting troubles.

The Iranian and Lebanese operatives killed by Israel in Syria were on the Syrian President Bashar al-Assad’s side of the civil war, which has claimed well over two hundred thousand lives in four years. There are foreign fighters who joined with Syrian rebels against Assad’s allies on the other side, too. Without the Syrian uprising, Al Qaeda would not have funnelled men into the country as readily as it did, men who largely abandoned Al Qaeda for its more radical rival, the Islamic State in Iraq and al-Sham (ISIS), after the two came into public conflict in April, 2013. Without Syria, ISIS, which had been flailing in Iraq for years, would not have been able to recruit men and money until it was powerful enough to declare a caliphate in parts of Syria and Iraq.

The ascendance of ISIS is fragmenting the region and, in many ways, changing the concepts of identity and citizenship in a Middle East that was already straining along socio-religious lines. Old borders mean less as new ones form within countries. During times of conflict, especially civil conflict, people fall back on their base identity, whether that is their clan, their town, or their sect: whichever identity is strongest and will best protect them. In some cases, that marker is hyperlocal. In others, it is transnational, an identification with a sect or an ideology.

In Iraq, the rise of the Islamic State reflects, in part, the failure of the local Sunni leadership to protect Sunni interests in the face of a Shiite-led government and rising Shiite militias. Until a viable Sunni alternative emerges, ISIS is unlikely to be defeated. In Libya, its supporters are among the plethora of well-armed militias fighting each other, tearing apart what remains of the state from the inside. In Egypt, the even stronger regime of General Abdel Fattah el-Sisi, which overthrew a democratically elected Muslim Brotherhood government, is a jihadi recruiter’s dream. By vilifying the relatively moderate Brotherhood, Sisi’s regime has helped to fuel the rise of the much more radical Sinai-based Ansar Beit al-Maqdis, which has pledged allegiance to ISIS. The phantom demon that the Egyptian state claimed to be fighting is becoming real.

Both ISIS and Jabhat al-Nusra, a Syrian group tied to Al Qaeda, have crossed into Lebanon, where they have local supporters. The two groups, which are rivals elsewhere in the region, are coöperating in Lebanon. They have declared the Lebanese Army a legitimate target because, they say, it is a Hezbollah-dominated and directed force. ISIS and Jabhat al-Nusra groups captured more than twenty Lebanese security forces in August, and most are still being held captive. (Four have been executed, some by beheading.) There have been car bombings in majority Shiite neighborhoods of Beirut, which the radical Sunni Islamists consider Hezbollah strongholds, as well as attacks on Army checkpoints. It’s a combustible situation, made more so by the influx of well over a million Syrian refugees into Lebanon, a country of four million people long divided over the issue of Syria, which occupied Beirut for twenty-nine years, until local and international pressure forced the Syrians out, in 2005. Even as Hezbollah fights alongside Assad, other Lebanese are supporting anti-Assad factions in Syria.

This brings us back to Hezbollah and Israel and the latest border attack. Hezbollah once enjoyed broad support in Beirut for ending Israel’s twenty-two-year occupation of southern Lebanon, in 2000. (Israeli forces were pushed back across their border, but remained in the Shebaa Farms area, the site of Wednesday’s ambush. Beirut and Damascus insist that the Shebaa Farms are Lebanese territory.)

When Hezbollah first admitted that it was fighting in Syria, in May of 2013, it lost a large part of its support in Lebanon outside of its main Shiite constituency. (That support had been dropping off since 2008, when Hezbollah briefly drew its guns on other Lebanese in a political dispute.) People feared being dragged deeper into their larger neighbor’s war. After the severity of the threat posed by Jabhat al-Nusra and ISIS in Lebanon became clear, Hezbollah regained some of that support, not because people believed that the group was right to fight in Syria but because the weak Lebanese Army was no match for the hardcore Sunni Islamists. Hezbollah is the strongest military force in the country, but it’s not clear that it can afford to reëngage along the Israeli front while it sustains losses in Syria and maintains only a precarious degree of support in Lebanon.

Wednesday’s ambush raised many other questions. Did Hezbollah now believe that it had settled its score with Israel, that this round was over? The two sides have exchanged rocket fire since the initial Hezbollah ambush, but questions remained about whether Israel would try to engage the group in a new war, stretch its resources, and precipitate an angry backlash against it in Lebanon. A new conflict could further erode support for Hezbollah in Lebanon; it’s also plausible that the Lebanese would grudgingly rally around the group as it battles its original foe, if Israel exacts collective punishment against Lebanon and not just against Hezbollah fighters.

During the 2006 war with Israel, southern Lebanese, who form the bulk of Hezbollah’s constituency, were sheltered by Lebanese in other parts of the country and in Syria. Where will those people find refuge if another conflict erupts? Can Hezbollah risk bringing out the mass internal displacement of Lebanese while the country is struggling to cope with the huge influx of displaced Syrians?

There are broader regional calculations as well. Both Hezbollah and Syria’s Assad are politically and financially backed by Iran. Plummeting oil prices must be straining Iran’s (and Russia’s) economic lifeline to Assad. A new Hezbollah front with Israel would make further demands on Tehran’s purse. Can Iran afford to foot Hezbollah’s bill? If Israel escalates the conflict, can Hezbollah choose not to respond without losing face? Is Israel just engaged in election-season muscle flexing? Would Hezbollah draw some of its forces back home from Syria to fight Israel, if that front reopened?

By Thursday, it seemed like the conflict along the Israeli-Lebanese border had died down just as quickly as it flared up. It’s not the first time a spasm of violence has been quickly quelled. It feels like a fool’s game these days to try and predict what will happen next, but it would be equally foolish not to see how the region's many conflicts are feeding into and off each other. It’s a messy moment in the Middle East’s history. At stake is nothing less than the nature of identities across the region, and the validity of new and old dividing lines—between and within states.