On Sunday, the G20 summit concluded in Hamburg with a lot of hoopla but scant results. Seen by many as an opportunity for Donald Trump to advance his international agenda, the gathering of world leaders petered out when it became clear that few, if any, were willing to follow the American President’s lead on issues ranging from climate change to global trade.

Trump’s decision last month to pull the U.S. out of the historic Paris Agreement on Climate Change was a particular sticking point in Hamburg. And so while the G20 released a communique on Saturday reaffirming its commitment to mitigating greenhouse gas emissions, the summit’s accord also included a paragraph on the United States’ individual efforts to combat the negative effects of global climate change. Some were even calling it the G19.

The struggles in Hamburg were the latest proof of the importance of international cooperation — and how hard it is to achieve. But political scientists tell us that even harder than agreement between nations is agreement within nations. Exhibit One on that front is the scene yesterday in Istanbul, where the Turkish opposition led by Kemal Kilicdaroglu concluded its 25-day sojourn across the country. Dubbed the “March for Justice”, Kilicdaroglu and his supporters walked more than 280 miles to protest the illegal detention of Enis Berberoglu, a member of Kilicdaroglu’s Republican People’s Party.

For the Turkish opposition, Berberoglu’s arrest and subsequent imprisonment is the perfect example of President Recep Tayyip Erdogan’s campaign to squash all dissent in a country that still claims to be a democracy. Kilicdaroglu delivered a rousing address on Sunday evening to an estimated one million people in Istanbul’s Maltepe Park.

As the Turkish daily Cumhuriyet reported, the crowds gathered under the word "adalet," or “justice”, for the tens of thousands of journalists, academics, and activists whom the Turkish state has arrested since last June’s aborted coup attempt. For Kilicdaroglu, yesterday’s rally was not an end to this struggle but rather its beginning, words cited on the front-page headline on Milliyet this morning.

The struggles in Hamburg were the latest proof of the importance of international cooperation — and how hard it is to achieve.

Internal troubles are also bubbling in the often capricious Middle East following Palestinian President Mahmoud Abbas’ decision last month to cut electricity to Gaza down to 2-4 hours a day. Although Hamas, the Islamist organization at odds with Abbas, currently controls Gaza, most of the small strip of territory’s electricity is controlled by the Israelis and financed by Abbas’ Palestinian Authority.

Most observers warn that the new electricity cut is a bellwether for a growing rift between the two Palestinian camps. But the summer row is also bound to feed eternal animosity toward Israeli policy. As Gazans suffer in the sweltering heat, Amira Haas, who covers the plight of Palestinians for the left-leaning Israeli daily Haaretz, writes that “in the absence of a single accepted leadership, in the absence of an agreed-upon strategy, coping relies on millions of individual schemes for survival and resistance using various types of efforts, energy and tricks.”

Haas calls it a “metaphor” for the entire Palestinian struggle. It’s also a reminder of what happens when leaders anywhere can’t figure out how to settle their differences.

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