Israel is a haven of democracy in a region of Islamic fascism. Some of those neighbours have vowed to push Israel into the sea. If any country on earth deserves the support of western democracies it is the state of Israel. The other great thing about supporting Israel is that they do a fantastic job of helping themselves.
On the other hand, the occupation of the West Bank is a disgrace. There are many times when Israel makes it very difficult for their friends to be supportive.
For a perspective from both sides see The Palestine - Israel Conflict by Dan Cohn-Sherbok & Dawould El-ALami or for the view of an Israeli who is critical of his country see Cursed Victory - A History of Israel and the Occupied Territories by Ahron Bregman. A good history of the formation of modern Israel is A Line in the Sand by James Barr.