But for the missiles, Israel would not have to take action against them.
IDF only targeted in that way confirmed combatants.
The Shin Bet 6 confirmed that.
Israel acted within the law, Hamas were guilty of indiscriminately attacking civilians, operating from civilian areas and placing people as human shields.

The 6 might be right that Israel's security was not improved, but Israel's actions in response to the missiles was restrained and legal.