Friday morning’s terrorist attack in Jerusalem’s Old City will be a huge test for the Palestinian Authority and the moderate Arab world. And it could go either way.PA leader Mahmoud Abbas’s condemnation of the attack which killed Border Police officers Haiel Stawi and Kamil Shnaan was encouraging. But the decision by the police to close the Temple Mount leaves open a wide array of reactions from the PA and the other Palestinian factions.It’s taken a lot less to ignite the Palestinian street, as has been witnessed from the first and second intifadas and last year’s stabbing and vehicular attack sprees.Will Israel’s response to Friday’s attack be the catalyst for another uprising? It depends on the Arab leadership. If PA leader Mahmoud Abbas, Jordan’s King Abdullah and other figures in the Arab world use the attack to urge calm, condemn terrorism and let Israel do what it needs to secure its citizens, then the incident will likely pass quietly and things will return to their usual low-level, tense reality.If, however, instead of focusing on the attack, the Palestinian and Jordanian reaction only condemns the Israeli response and decries the military suppression and the lack of religious freedom for Muslims in Jerusalem, it’s bound to light a fire.And if they take it further by flagrantly warning that the Israeli measures are a cover for taking over the Temple Mount, all hell could break loose.It’s only July and the Middle East heat has been unbearable. Will things heat up further in August? It appears that it’s going to be up to the Palestinians.