Gaza will not be another Vietnam.

Hamas will not become an invisible enemy as Israel knows who they are.  The Mossad database is up to date.  And the people of Gaza are not sympathetic with Hamas so, the entire population is not the enemy.  In fact, they may even see the Israelis as liberators and collaborate with them.

It will be a well defined mission with the objective of taking down Hamas' command and control structure.  Tactics will involve checkpoints and sweeps.  The barrage of missiles and rockets will be neutralized and no new installations will take place.

And if Egypt comes in to assist their brother muslims, then Israel will route their armies again.