An announcement by North Korean leader Kim Jong Un that his country will stop testing nuclear weapons and intercontinental ballistic missiles is a sign that Kim is ready to do a deal with Donald Trump -- and that he understands how a deal with Trump can be made. Its a delicate dance that Russian President Vladimir Putin and the leaders of Iran are no doubt watching closely. Even before the US enters an agreement with North Korea, its very willingness to talk signals the primacy of pragmatism over principle. The US may stand for certain values, but they take a back seat to its interests. In North Koreas case, the interests are basic: the elimination of a North Korean nuclear threat to US territory and the mitigation of tension on the Korean peninsula, where the US has an important ally, South Korea. Though the Kim dynasty has eliminated many more Koreans than the al-Assad dynasty has killed Syrians, though the US doesnt even have diplomatic relations with the North Korean regime, and though Kims father and his grandfather have proved time and again that they dont play by Western rules -- the US is still willing to talk. Once ideological motivations are discarded, three conditions made the Kim-Trump talks possible: South Korean President Moon Jae-Ins desire to pursue closer ties with the North; Kims ability to assert victory (after all, the US wouldnt have come to the negotiating table if not for his successful missile tests); and Trumps ability to claim victory as well (he can say he forced Kim to negotiate by threatening "fire and fury" and then boosting economic sanctions). Whether these conditions are also sufficient remains to be seen. Kim could overplay his hand by demanding that the US drastically reduce its military presence in South Korea, and Trump could hold out for a full North Korean denuclearization, (which he appears to believe is on offer instead of a stop to testing), rather than an internationally controlled freeze on its weapons program. The outcome would depend on both negotiators continued ability to lay a convincing claim to victory. What, then, if a similar combination of circumstances could set the US and Russia on a path toward a deal that would end the current iteration of the Cold War? Such a deal would need to address Ukraine (but not necessarily Syria -- more on that later), clear rules of cyber engagement, mutual electoral noninterference, and curbs on both anti-missile defenses and means of breaking through them. If Trump and Putin began talks on all these issues, Putin would be able to sell this as his win -- finally, hed say, the West has heard his threats of superweapons and realized that it can no longer ignore Russia as a declining regional power. Trump, too, would be able to tout a win after hitting Russia with tougher sanctions than his predecessor and generally standing up to Putin -- while also keeping the possibility of a deal open. And yet, the timing isnt right. One thing missing is a Ukrainian Moon Jae-In, someone willing to implement the political part of the long-suffering Minsk agreement and reclaim the bits of Ukrainian territory held by Russian proxies on the softest possible terms. Ukrainian President Petro Poroshenko is severely constrained as he consolidates power to set up his reelection in 2019. Ukrainians wont elect anyone even remotely dovish on Russia in the immediate future: The two countries conflict is too fresh, unlike the Korean War. And without a local dove, the US, too, is constrained since not even Trump can afford to be seen aiding Russias dismemberment of a neighboring country. Realistically, whats also missing is a US Congress open to a deal. There is no political capital to be won by going soft on Russia now. In a way, Putin is in a worse situation than Kim, though Russian-American relations, even at their lowest point in decades, are still better than US-North Korean ones. The Russian ruler is a hostage to his relative success in Ukraine; he must hold on to keep looking like a winner. Similarly, he cannot give up on backing Assad in Syria -- thus Foreign Minister Sergei Lavrovs announcement on Friday that Russia will supply Assad with S-300 air defense systems. Putin needs a third party to bridge the distance between him and Trump but none exists, so he has to pretend he doesnt really want a deal, even though most Russians, including many in the Kremlin, would heave a sigh of relief if it were made. If the Kim paradigm works, however, why not a new deal with Iran, this time focusing on curbing Irans regional ambitions? The US could, to take a thought experiment, let Iran keep its influence in Syria and Lebanon in exchange for recognizing Israel and dropping the support of Houthi rebels in Yemen. Then Russias Syria meddling would become a non-issue and separate talks about it with Putin wouldnt be necessary. Putin and his Iranian allies would simply finish their job in a country where the US doesnt want to fight a land war regardless of whether a Democrat or a Republican is in the White House. To do that sort of deal, the Iranians need to be able to claim a victory -- and they would be, since theyd be recognized as a legitimate player in the Middle East and get access to improved economic growth opportunities. Trump, too, would be able to boast that his pressure worked. But there needs to be a key US ally in the region to become much more dovish towards than it is today. 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