Actually that’s not true, the muslim Arab countries went to great lengths to intervene and support the Palestinians. From starting coalition wars that sought to destroy Israel to organized boycotts and sanctions by the muslim world to placing diplomatic pressure on the West to put out peace proposals to giving them billions in aid annually. They tried everything, but every time, the Palestinian leadership has insulted them, backstabbed them, lied to them, or squandered their efforts away. For example:

Jordan - Took part in coalition wars, took them in as refugees… but Palestinians used this as an opportunity to try to overthrow the Kingdom by assassinating officials and committing terrorist attacks. It was so bad that these events became known as black September.

Egypt - Took part in the coalition wars, tried to diplomatically support Palestine, and took them in as refugees… but the Palestinians also took this as an opportunity to try and overthrow the Egyptian government multiple times. It got so bad that Egypt had to join Israel in their blockade.

Kuwait - provided military, economic, and political support as well as took them in as refugees… but the Palestinians openly celebrated and supported Iraq’s invasion in the 90s under Saddam Hussein. It got so bad that Kuwait kicked out all 350,000 Palestinian nationals from it’s territory.

Syria - Took part in the coalition wars, provided diplomatic support, and took them as refugees… but the Palestinians ended up trying to overthrow the government during the Syrian civil war. It got so bad that Bashar Al Assad pretty much severed relations with them.

Saudi Arabia - I don’t even need to say anything here, they literally released a 3 part documentary (that I highly recommend) that goes through everything they did to support the Palestinians and what they did in return. Here’s part 1:

http://m.youtube.com/watch?v=edKZbu5OM1c

I could keep going, but I think you get the idea. There’s a reason why all these countries are starting to recognize Israel now. They tried everything in their power to act on the behalf and in the best interest of Palestine, but in the end their efforts just blew back in their faces