TEL AVIV — AFTER nearly three weeks of fighting — notwithstanding the 12-hour pause announced early this morning by Israel — it is time to revisit some basic assumptions about Hamas. Until now, Israel assumed Hamas was the “devil we know,” capable of attacks that were mostly a nuisance; accepting its rule over the Gaza Strip was preferable to risking a vacuum of governance like what we see in Somalia and Libya. But Hamas’s reckless violence in the current round of fighting severely undermined this thinking.

First, Hamas has proved a bad ruler. By placing many of its military assets — tunnels to infiltrate Israel, bunkers for its fighters, rocket launchers to terrorize Israeli civilians — under or among mosques, hospitals and schools, Hamas turned Gaza’s civilians into a shield for its military assets, in effect daring Israel to attack them. Then it cynically turned the predictable casualties that ensued into propaganda, and rejected cease-fire proposals, notably an Egyptian plan accepted by Israel, the Arab League and the international community. Last week, Mohammed al-Arabi, a former Egyptian foreign minister, accused it of “shedding the blood of innocent Palestinians.”

The latest round of warfare showed that Hamas had become more dangerous, and its offensive capacity stronger, than we had known. Its ability to threaten Israeli towns through its tunnels and to rain rockets on Israeli cities raised what had been a nuisance to a challenge of strategic proportions.

For these reasons, Hamas’s rule over Gaza must be brought to an end, its military wing disarmed, and Gaza’s people given the chance to elect new leaders.