Regarding Vietnam, you can't ignore how terrible south Vietnam's governments were.
When Ngo Dinh Diem started jailing Buddhists in 63, and then closed all universities and schools and people were lighting themselves on fire in the streets in protest of him, we should have withdrawn right there and said "we can't support this guy."
Bombing campaigns don't win wars.
Boots on the ground do.
But if you aren't willing to send those boots where they need to go (after Korea, we were not going to invade NV) then you need to be realistic about what can and can't be accomplished.
Regarding Hamas… Israel needs to decide if it's willing to occupy the Gaza Strip to eliminate Hamas. And if it is, then what's the exit strategy and what losses are acceptable? Israel is so bad at PR that the bombing campaign is arguably doing it more harm than good. But sending troops into a heavily populated urban battlefield that Hamas has had 15 years to prepare is a recipe for tremendous Israeli casualties. And there's still the question - ok, you kill Hamas, what about Islamic Jihad? What about the next group that takes Hamas's place? How do you keep that area secure?
But the what's the cost of doing nothing? Then you're just waiting for Hamas to strike again. That is unacceptable.
There are no easy answers. But israel needs to play the PR game better. War is just politics by other means. Israel needs to remember this - what is the objective? Better PR needs to be part of the strategy.
Thanks and gig'em