After five months in power, Greek Prime Minister Alexis Tsipras has 48 hours to make a decision that will shape his country’s future for decades, yet his negotiating partners cannot be sure which way he will jump. The 40-year-old leftist, elected in January on a promise to end austerity, must decide whether to swallow an unpalatable deal with international creditors to avert a default next week at the risk of losing part of his Syriza party, or refuse and risk economic chaos and ejection from the euro zone.