Lebanon is in turmoil again today, but this time the turmoil is clearer than it has been in the past. As things stand right now, members of Hezbollah are thugging their way through the streets of Beirut, setting fires, fighting, and dumping piles of dirt and trash in the roads in order to shut down the city. Most importantly, Hezbollah has closed the highway that connects Beirut to Lebanon’s major airport.

All of this is in response to a few brave and necessary actions recently taken by the Lebanese government. The cabinet voted to dismiss the Beirut airport security chief, a Hezbollah loyalist who allowed the group to set up a video surveillance system to monitor the airport. The government also ordered a judiciary probe of the independent telecommunications network that Hezbollah has been building, with Iranian assistance, in recent months.

So Hezbollah has responded by doing what it does best: sowing chaos and violence, escalating its confrontation with the Siniora government, and hoping that when the dust settles Siniora is weakened (or even removed from power) and Hezbollah is on stronger ground.

The flashpoint to watch is the airport road. Lebanon, like Israel, has only one major airport (although there is talk of quickly turning a smaller airport in the north into a functioning international hub), and its closure is debilitating and unacceptable. The Lebanese government faces the grave and immediate question of whether to capitulate to Hezbollah or to send troops to open the road, which Hezbollah has been covering with truckloads of landfill. Siniora says that his government will not back down; Hezbollah says that it now considers the Lebanese army as having “joined the enemy,” and might build a tent city on the airport road, just as it has done in downtown Beirut.

Hezbollah, though, is isolated in Lebanon as never before. In its latest tantrum, it operates without the sectarian cover of its erstwhile Christian ally, Michel Aoun; the fight is now more clearly than ever one of Hezbollah vs. Lebanon, rather than one of some Lebanese groups vs. some other Lebanese groups. This is bad for Hezbollah, because it puts them in a corner in terms of political tactics — there will be no alliance-shuffling and dealmaking in the offing, always the hallmarks of Lebanese crisis-management — and because it puts Nasrallah in a win/lose corner: either he forces the government to capitulate, or he is seen as having been defeated.

And Hezbollah’s military options against the Lebanese government aren’t clear, given that Hezbollah has organized itself to fight a rocket and guerrilla war against Israel, not street battles in Beirut. If Hezbollah forces an armed conflict, its fealty to Iran and fundamental hostility to Lebanon will be laid bare as never before. Stay tuned.