ISTANBUL – In Turkey, where President Recep Tayyip Erdoğan’s government has been working to centralise political power, opposition parties have lately had few reasons to be optimistic. This month’s massive rally in Istanbul was a rare exception.On July 9, after walking for 25 days from the capital, Ankara, Turkey’s main opposition leader, Kemal Kiliçdaroğlu, urged supporters to resist the decline in democratic freedoms.