Legally Israel has the right to apply blokade. This is one fact! But on the other hand, politically Israel's blokade can bring no solution to the problems of the region. In the course of human history there have been many acts like Israel's, the most recent being the wall of Berlin, where we have seen that segregation only leads to social and economical unbalance and this eventually leads to an accumulation of hatred and social distruption. Israel's current political views are already burried in the first half of 20th century. 20th century was an age of nation states, wars and WALLS 21st century is the century of globalization, where politics surpasses wars.
The blockade of Gaza is worsening an already desperate situation... and history shows that desperate situations results in desperate solutions. One can't blame Palestinians for their hatred toward Israel, the way they have been abused over the years. Of course there will be some form of resistance from their side. Israel can't use that as an excuse, when in reality, they are the ones fueling the terrorism.
Is Israels bombing of civilians any less terrorism, just because it's dropped from a helicopter? I don't think so. The people of Gaza can't even leave!
Personally I don't think the state of Israel ever should have been made. The land belonged to the Palestinians, but was colonized by Britain. They had been promised their land back if they assisted Britain in the war - which they did. But Britain didn't keep their promise. After WW2 they didn't have the resources to keep it, so they left the responsibility over to UN. Which decided in sympathy for the Jews, as a result of Nazi-Germany's brutal treatment, to hand the territory over to the Zionists.
Now they have their land... there's no turning back. We have to accept that. But the Israelis (note that I'm not saying "Jews", but Israelis - so don't scream anti-antisemitism) still got the nerve to abuse the Palestinians, by forcing them out of their most sacred city. They are building illegal settlements, marginalizing the little of what the Palestinians have left... taking political prisoners, abusing people's rights, and blockading an already devastated area with one of the world's most dense population - hindering them from retrieving the ever so needed help.
So yeah... I'd definitely say that Israel has no right in blockading Gaza.
I'm pretty sure it is not illegal of them to have a blockade. I'm still figuring out the facts about all of this, though. I just think everything going on over there isn't being handled well on all sides.