Una breve "introduzione" ad opera del Council on Foreign Relations.
"Is Israel legally allowed to use force to find its soldiers?
Yes. Israel is well within its right to protect its nationals abroad and to defend itself with the use of force, as authorized by Article 51 of the UN Charter. Experts say Israel has a legitimate case—it was preemptively attacked by Hezbollah. Less clear from a legal perspective is what kind of force is acceptable. "The U.S. concluded that the attack on Pearl Harbor necessitated overthrowing the Japanese government," Glennon says. "Strictly speaking, would the doctrine of proportionality have permitted only a tit-for-tat response? That’s one of the uncertainties the doctrine presents."
An important factor is the scope and scale of Israel’s mission. "Is the key to what they’re doing tailored to the mission of getting the soldiers back? That’s the question," Newton says. He says that offensives carried out by Israel must be related to the military objective of rescuing its soldiers, not exacting punishment on the Lebanese or Palestinian populations. But under certain circumstances, its mission could be expanded to prevent Hamas or Hezbollah from carrying out future cross-border attacks or seizing more soldiers.
Is the Lebanese government responsible for the abducted soldiers?
Yes. Israel is correct to hold the Lebanese government responsible for their protection, despite the fact they were captured by Hezbollah, a minority faction within Lebanese politics. "There’s a longstanding principle of international law that states may not permit their territories to be used for activities that harm another state," Glennon says. Short of the use of force, Israel may respond legally by retorsion—any countermeasure taken by one state against another, regardless if an illegal act has been committed—which may include a severing of diplomatic ties or possibly sanctions."