JERUSALEM — For years, he was a distant adversary, overseeing attacks on Israeli and Jewish targets abroad. But as time went on, the threat from Maj. Gen. Qassim Suleimani loomed ever larger and closer for Israel.

So the assassination of the Iranian commander in an American drone strike in Baghdad early Friday was greeted with satisfaction in Israel, though also with a degree of caution as the country went on alert for possible retaliation.

General Suleimani, who led the Quds Force of the Islamic Revolutionary Guards Corps, oversaw an Iranian program to surround Israel with tens of thousands of missiles, according to experts.

He was also the architect of Iran’s recent entrenchment in Syria and of an ambitious plan to build an Iranian front against Israel across its northern frontier, in the Golan Heights.