It is bitter truth that Pakistan Army will not fight for Palestine against Israel because in international law it is mentioned that no government will help any state in the war between two other states. If we see the history of Pakistan then we come to know that Pakistan has always remained neutral but our army has participated in the UN missions. Pakistan will support Palestine if the UNO demands Pakistan but the United Nations will not start any mission in favour of Palestine because the UNO even doesn't accept Palestine as a sovereign state so how the UNO will start mission on Palestine soil? If any member of security council say to start mission in Palestine then most probability is that the USA or the UK will veto against it.
We gave Pakistan soil to the USA for Afghan war because we hadn't any choice but due to our neutral foreign policy we didn't involve in Iraq war and Kuwait war and even we didn't involve in Palestine war in the past.