Political movements change. They sometimes change profoundly. The US Democrats went from "the party of slavery" to "the party of civil rights" in the space of a hundred years. In a similar space of time, the UK's Liberals went from being a party led by a Prime Minister (HH Asquith) who took the country into the First World War, promoted imperialism and opposed votes for women to being today's progressive Liberal Democrats. South Africa's National Party, the party of apartheid, evolved into the conservative, democratic New National Party and forged an abortive alliance with the liberal Democratic Party before merging into the movement that had most opposed apartheid, the African National Congress.
So, given that organisations can change (and can change rapidly), I accept that, in theory, Hamas could change, and could evolve from its current role as the Ku Klux Klan of Palestinian politics (http://matthewfharris.blogspot.co.uk/2011/05/talking-of-adverts-see-this-one-about.html) into something more hopeful - into a body that could actually have something useful to contribute to the peace process, in contrast to its current commitment to the destruction of the State of Israel.
Indeed, I am regularly reading and hearing reports that this or that element within Hamas has made precisely such a change, usually swiftly followed by a declaration from the movement's leadership that there has in fact been absolutely no change and that Hamas will not allow Israel to exist within any borders whatsoever. If you read http://www.timesofisrael.com/hamas-official-denies-group-could-recognize-israel/, you'll see that a Hamas official reportedly recently even threatened to sue The Washington Post for libel after the paper had quoted him as saying that Hamas might recognise Israel.
Despite the dispiriting experience of all these hopeful noises from Hamas having been retracted as swiftly as they were uttered, I have maintained an open mind about the possibility that even the most disgusting and dangerous of political entities could possibly change, given what history teaches me about Nazi Germany's swift transition into West Germany, Imperial Japan's equally swift evolution into democratic Japan and Egyptian President Anwar Sadat's journey from starting the Yom Kippur War in a bid to destroy Israel, to making a lasting peace with Israel only a few years later.
Given my maintenance of that open mind and my concomitant willingness to listen to those friends and colleagues who tell me that Hamas is on some sort of road to peace and reasonableness, you can imagine my irritation, disappointment and disgust at reading the following (http://m.bbc.co.uk/news/world-middle-east-27863465): "Palestinian officials have said they are co-operating with the search (for the three missing Israeli teenagers) - a move Hamas has condemned."
Three teenagers go missing, presumed kidnapped. Palestinian officialdom (which, to put it mildly, has no great love for Israel), extends the normal assistance that any decent human polity would offer to any other polity that was searching for three missing young people, and what does Hamas do? It does not support this assistance, it does not remain silent on this assistance, it does not even say "We hate Israel, but obviously we still want these kids to be found safe and well" - no, instead, Hamas actually condemns Palestinian assistance for the Israeli search for the missing boys.
Contrast this with the help extended by Israeli hospitals (and the people who work in them) to Syrian people wounded in that country's brutal civil war, despite Syria being a country that does not recognise Israel and which chooses to remain in a technical state of war with Israel: http://mobile.nytimes.com/2014/01/30/world/middleeast/despite-decades-of-enmity-israel-quietly-aids-syrian-civilians.html?referrer=&_r=0. That same article also says: "Israel's defence minister, Moshe Yaalon, said this week that Israel "cannot remain indifferent" and had been providing food and winter clothing to Syrian villages across the border fence as well as tending to some of the wounded."
For Hamas to become a body that has anything useful to contribute to the peace process and the Palestinian cause, it has to adopt that same basic humanitarian instinct.