As we have been told that the war to destroy Hamas may last months, a simple strategy to reduce IDF casualties and to get Hamas to surrender comes to mind. Why not flood the tunnels with Mediterranean Sea water? In the entire month since the war started, I have not heard this idea discussed. Why not?
Gaza City borders the Sea. If the IDF is in control aboveground, can its engineering battalion construct a method of pumping sea water into the tunnels? It would certainly take time to build the apparatus needed to do that. However, it may be relatively easy to defend and protect IDF soldiers while they are covering the engineers.
Drowning is a particularly undesirable way to die. I doubt that any Hamas or Islamic Jihad member would relish the thought. Perhaps, they would surrender more quickly once the flooding of the tunnels became a reality. At the same time, in order to save their own lives, perhaps they would be more convinced to release the hostages. Worth looking into, no?