I listened to the Trueanon episode with Norman Finkelstein and I think he articulated things pretty well. Basically what else were they suppose to do? If they'd broken out of the fence and then threw down their guns and stood waving protest signs there they'd have been massacred and Israel would have claimed they were armed.
If they'd broken out then all ran away, Israel would have launched a massive effort to hunt them down and kill them and it would have been pointless, no liberals would have done anything, it would have been ignored (he brought up how some Palestinians escaped a maximum security prison, got back to Gaza and there was celebration, until within 48 hours the Israelis had murdered all 3 of them).
They tried the whole peaceful approach in the great march of return, they were gunned down, snipers murdered kids, they shot out people's knee-caps condemning them to joblessness, a life of no prospects and suicide. So what else were they supposed to do? And the only answer that makes sense from liberals who support this is to quietly sit there and die so the liberals can later feel badly about it.
So there's only one bad side. And it's the side that hasn't taken peace or giving the Palestinians a state seriously. It's the side where western governments ignore horrendous atrocities against children for years, decades, openly documented with video and photo evidence, they don't pressure Israel to do anything in all that time other than maybe hide it better. It's the side that ignores settler terrorism.