For years there has been an argument about whether Israel should risk its soldiers to protect the lives of Palestinian civilians. The age-old question was best highlighted during Operation Defensive Shield, when 13 soldiers were killed because the IDF did not want to risk civilian lives by using bombing the refugee camp. In fact, Israel could have likely protected all of its soldiers by bombing from the air, rather than embarking on a house-to-house campaign.
Moreover, assuming a country should risk it soldiers to protect enemy civilians, what constitutes a civilian? Is a civilian someone who stays out of the fighting, or someone who doesn't participate in the war effort in any way? Or maybe only someone who in no way benefits the army? The latter definition would deny the existence of civilians because anyone who is part of a country participates in the economy and therefore is helps the warring country.
I would support the broadest definition possible, which, assuming there's a duty to protect civilians, would lead to the greatest amount of protection for the greatest number of people. I support that definition for the same reason I believe there is a duty for soldiers to risk their lives to protect enemy civilians: because it minimizes the loss of life in war.
Eyal Benvenisti argues that civilians have a right to life and cannot be killed with impunity. However there is no universal obligation to protect that right. Therefore the requirement for combatants to spare enemy civilians is rooted in reciprocity agreements that expect both countries to leave civilians off-limits. In essence, Benvenisti posits an implicit agreement between the warring parties to keep civilians out of the fighting.
This is the essence of the current dichotomy between combatant and civilian. Combating parties agree to not harm civilians in exchange for protecting their civilians. This agreement is actually multilateral in that all countries and groups agree and that creates a binding obligation on all the parties.
Obviously not all countries will abide by the agreement. For example, if Israel was at war with Syria, it seems unlikely that Syria would be as careful about protecting civilians as the IDF. But this agreement has shifted what's acceptable to the more humane. Fifty years ago, bombing civilians was allowed even by democratic countries. Today, countries are much more wary about attacking civilians. The agreement has made it more difficult for a country like Syria to bomb indiscriminately (although there are other reasons why countries might abide by international law).
Breaking the agreement would legitimize attacking civilians. If Israel decided to indiscriminately bomb Jenin, it would make intentionally killing civilians more acceptable. While terrorist groups continue to murder civilians as their primary goal, the world (although not all countries) views such tactics with disdain. The less acceptable a tactic is, the less support a group will have for using it.
Take Hamas as an example. After the recent terrorist attack Denmark (Denmark!) cut off aid to the PA. It might be acceptable to support terrorism indirectly, or not combat it, but it is no longer acceptable for a group to use it. That is an important shift in the right direction.
So, in some cases, risking soldiers will benefit civilians. And since the purpose of soldiers is to protect civilians, perhaps the risks are justified.