Recep Tayyip Erdogan and Mr. Putin, nationalist autocrats, were in Tehran for a tripartite summit with their Iranian hosts to discuss Syria and other security and economic issues, including Russia’s ongoing war against Ukraine. The summit, officially part of a series of talks on the future of Syria, was unofficially a diplomatic counterpoint to recent visits by United States President Joseph Biden to Israel and Saudi Arabia. In many joint statements and press appearances, there was little evidence of any breakthroughs on regional issues, including a proposal to allow Eastern European food out of the Black Sea conflict zone and into world markets. But each leader could claim a measure of success. Turkey underlined its diplomatic weight as an associated member of several regional geopolitical axes. Both Iran and Russia have forged a partnership that has rankled the West, particularly Washington. “Whether President Putin’s trip advanced any of his key goals in Ukraine, Syria or elsewhere remains to be seen,” the Soufan Group, an intelligence and security consultancy, wrote in a note distributed to subscribers. “However, the Russian leader was able to demonstrate that US efforts to ostracize and isolate him in the region were unsuccessful.” Each nation had its own reason for participating in the summit, which ended late on Tuesday. Both Iran and Russia seek to emphasize their cooperation at a time when the US seeks to isolate both. Turkey has sought to persuade Iran and Russia to prevent its possible imminent attack on Kurdish-led armed groups and American-aligned political organizations in northern Syria, which it sees as a threat. Both Mr Putin and Iran’s Supreme Leader Ali Khamenei warned Erdogan not to attack. Mr Putin’s visit was only his second abroad since he launched the war against Ukraine five months ago, and his presence was intended to underline US efforts to isolate him. In Mr. Khamenei, Mr. Putin found another world leader who endorsed the muddled Russian narrative of the attack on Ukraine, which has left thousands of Ukrainian citizens dead and shows no sign of resolution. “If Russia had not taken the initiative, the other side would have provoked a war on its own initiative,” Khamenei was quoted as saying. The video of a clearly bewildered Mr. Putin awkwardly waiting for Mr. Erdogan was in stark contrast to the image of the leader of a critical nuclear power his handlers tried to portray. The video went viral on social media and was highlighted by the Turkish press, which described it as payback for a 2020 meeting that Mr Erdogan has put on hold. “Mr Erdogan wins revenge,” read one headline that topped an article on the Oda TV news site. Mr Putin, who was raised as a self-confessed hoodlum in St Petersburg, has become notorious for keeping world leaders waiting in less than tasteful exercises to consolidate his rule. But the war in Ukraine has diminished his stature, and where world leaders once sought his tutelage, Russia now appears to need its partners more than they do. Iran has experience avoiding sanctions that Russia may need as it faces severe restrictions on its banking, exports and imports. Iran’s domestic military industry has also grown formidable, and US officials claimed that Russian military personnel watched two demonstrations of Iranian fighter drones earlier this month ahead of a potential purchase. But Kremlin adviser Yuri Ushakov told Russian media that Putin had not discussed with his Iranian counterparts the possibility of buying Iranian drones, as US officials have claimed. He did not comment on whether members of his delegation, many of whom arrived in Tehran the night before, discussed the military issue.