Just when you thought that the Middle East couldn’t support yet another crisis — after all, there’s Iraq, Iran, Afghanistan-Pakistan, and throw in Georgia, too — the Syria-Lebanon front is heating up. This is serious stuff.

Breathless neocons are issuing alarmist warnings about a possible Syrian invasion of northern Lebanon, after a spate of bombings that hit both Damascus and the northern Lebanon city of Tripoli. Amir Taheri, one of those neocons, writes:

For the last week or so, Syria has been moving heavily armed elite military units to the Lebanese border – with up to 25,000 massed there by early last week. Backed by tanks, armored vehicles and attack helicopters, the units were on “maximum war footing,” eyewitnesses say. … Lebanese analysts say the type of force Syria is massing is better suited for a classical invasion than for chasing small and scattered groups of bandits along the border.

According to the Lebanese media, Syria has placed about 10,000 troops on the border.

This comes at a critical time: Israel and Syria are conducting fairly public negotiations about a Syrian-Israeli deal to return the Israeli-occupied Golan Heights to Syria, and the leaders of both Turkey and France are deeply engaged in promoting it. At the same time, Syria is closely tied to Iran, and Syria’s President Assad is getting stronger backing from Russia, including arms, since Syria supported the Russian action against Georgia. It all means that this is a high-stakes game.

Some background: earlier this week, a huge car bomb in Damascus killed 17 people, not far from two possible targets: a headquarters of the Syrian intelligence service and an important Shiite mosque. Both targets are plausible for attacks by underground, Sunni fundamentalist radicals — possibly tied to the Syrian Muslim Brotherhood — who oppose Assad’s regime. (Many Sunni fanatics consider Assad, who belongs to a quasi-Shiite minority sect, to be an infidel.) The bombing took place against the backdrop of an ongoing insurrection by Sunni Islamist prisoners in a Syrian jail.

According to the Times, Assad put the blame on Islamists based in northern Lebanon and moved troops to the border:

Assad issued a warning about the presence of hard-line Sunni Islamists just across the border in northern Lebanon, hinting that they were receiving support from Saudi Arabia. Subsequently, thousands of Syrian troops were deployed near the border with northern Lebanon, in a move that was understood as a related gesture, though Syrian officials said it was to control smuggling.

Here’s the actual quote from Assad:

“Northern Lebanon has become a real base for extremism and constitutes a danger for Syria.”

Assad also hinted, reports the Times, that Saudi Arabia — whose regime notoriously supports both the Muslim Brotherhood and Sunni extremists in Lebanon — might be behind the bombings and Islamist revolts.

In and around Tripoli, there is a proxy war of sorts underway, pitting hard-core Sunni Islamists against secular, nationalist and pro-Syrian forces there.

Lebanon’s political system, of course, is fragile. Earlier this year, a breakthrough accord was reached around the election of the army chief of staff, Michel Suleiman, to be president of Lebanon. As part of the deal — which was brokered by Saudi Arabia and Iran, working together — the Iranian-backed Hezbollah militia was granted a powerful place in Lebanon’s government. And Suleiman began tilting toward Damascus. Many neocons raised alarms, worrying about the possibility that the influence of Syria and Iran was giving those two powers, and Hezbollah, a controlling share in Beirut. Is it possible that the deal is unraveling? Or will Syria, Iran, and Hezbollah simply opt to exercise a coup d’etat in Beirut (and Tripoli)?

The Syrian foreign minister, Walid Moallem, didn’t tip his hand in an interview this week in the Wall Street Journal:

The visit of President Michel Suleiman to Damascus last month was an important visit. It was agreed to build a strong base for the future of relations between Syria and Lebanon, starting from exchanging diplomatic relations, demarcation of the borders, and security cooperation between both countries. These issues are important and build on the mutual respect for sovereignty and independence of both countries.

Last Friday, Moallem held an unusual meeting with Secretary of State Condoleezza Rice.

The US establishment certainly doesn’t want a war with Syria. But more radical elements, from the neocons to Israeli hardliners to Saudi backers of anti-Syria Islamists, might be pushing the crisis. The Syrian exiled opposition, led by the Muslim Brotherhood and a former top Syrian official, Abdel-Halim Khaddam, have long been rumored to be in discussions with US and French intelligence about “regime change” in Damascus. But on the ground, in Lebanon at least, Syria seems to be in the driver’s seat.