Beirut has been here before. Campaigns of targeted assassination have often killed Lebanese bystanders, a price they must pay for living in the constant state of near-instability since the end of the civil war in 1990.
Twenty-one people, in addition to the former prime minister Rafiq Hariri, were killed in the February 2005 blast that reshaped Lebanon's politics. As a direct result, Syria's military dominance in Lebanon came crashing down. The "Cedar Revolution" of peaceful protest united tens of thousands of Lebanese from across the political spectrum. They expressed their revulsion, and their certainty that Syria was the culprit, with such force that the pro-Syrian cabinet could only resign. By April, as international condemnation poured in, Damascus pulled its 15,000 troops out of Lebanon.
It was all very dramatic, but everyone knew that Hizbollah, Syria's client and proxy, remained deeply rooted in Lebanon. In 2011, a UN Special Tribunal officially confirmed what everyone knew: Hizbollah agents had a key role in killing Hariri.
And now everyone in Lebanon knows - although there is so far no proof except the old test of "who benefits?" - that Hizbollah was in some way involved in this latest bombing, last Friday, that killed General Wissam Al Hassan, the intelligence chief of the Internal Security Forces.
Has the party overplayed its hand? Large demonstrations yesterday denounced the killing. Across Lebanon, there are demands that the militia be disarmed, and that the bombers be brought to justice.
Many anti-Syrian politicians and journalists have been killed over the years in Lebanon, but this time may be different. The regime in Damascus has been greatly weakened by 18 months of civil war. Unconfirmed reports say Hizbollah has sent men east to fight with the Syrian Army.
Even weakened by public outrage, however, Hizbollah has such a power base in Lebanon that it will not collapse anytime soon. And Lebanon's political structure is more like a willow than a cedar - enormously supple, it bends with the wind. Prime Minister Najib Mikati, known as moderately pro-Syrian and supported for the post by Hizbollah, has offered to resign, but remains in office for now.
Hizbollah's weapons have distorted Lebanese politics for more than three decades. No government can be healthy when factions operate private armies. Despite Damascus's troubles, it still wields undue influence in Beirut. But the era in which Hizbollah could blow up its political enemies with impunity may be coming to an end, and that would be a clear improvement for Lebanon.