In this task, you are given a text of many news articles seperated by special token "|||||". Your task is to summarize them.
Q: Mr. Trump said he was open to allowing Japan and South Korea to acquire nuclear weapons to deter their rogue neighbor, North Korea. He also declined to rule out using nuclear weapons in a military conflict in Europe, saying, “You don’t want to, say, take everything off the table.” 
  
 He first broached the issue of a nuclear-armed Japan and South Korea in an interview with The New York Times last week, putting it in the context of his case that the United States should no longer bear the full burden of defending its Asian allies. He defended his comments in a town-hall-style meeting on Tuesday in Milwaukee, televised by CNN. 
  
 “You have so many countries already — China, Pakistan, you have so many countries, Russia — you have so many countries right now that have them,” he said. “Now, wouldn’t you rather, in a certain sense, have Japan have nuclear weapons when North Korea has nuclear weapons?” A senior Japanese government official quickly reiterated that it was Japan’s policy never to possess nuclear weapons. 
  
 On Friday, Mr. Obama described the alliance with Japan and South Korea as “one of the cornerstones of our presence in the Asia-Pacific region” — one that was paid for with the sacrifices of American soldiers during World War II, one that has expanded American influence and commerce and one that “has underwritten the peace and prosperity of that region.” 
  
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 “You don’t mess with that,” Mr. Obama added. 
  
 In summarizing the accomplishments of the Nuclear Security Summits — this was the fourth and final one of his presidency — Mr. Obama acknowledged a tension between his emphasis on nonproliferation and the American military’s relentless efforts to improve the efficiency of its existing stockpile of nuclear warheads. These American technological advances rattle Russia and China, which cite them as a pretext to develop their own new weapons. 
  
 “I’ve tried to strike the proper balance,” Mr. Obama said. He noted that he had tried to negotiate a further round of arms reductions with Russia after the New Start treaty. But the return to the presidency of Vladimir V. Putin ended those prospects. In the meantime, he said, the United States needed to make sure its stockpile was “safe and reliable.” 
  
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 Mr. Putin boycotted this meeting, which foreclosed the possibility of ambitious agreements, since Russia is one of the world’s two largest nuclear-weapons states, along with the United States. 
  
 Earlier on Friday, Mr. Obama argued that his marquee accomplishment in nonproliferation — the nuclear deal with Iran — had “achieved a substantial success.” Because of restrictions that the deal imposed on Iran’s nuclear program, he said, it would now take the Iranians about a year to build a bomb — if it breached the deal — as opposed to two to three months before the diplomatic effort began in mid-2012. 
  
 Asked about reports that the Treasury Department would allow Iran to conduct transactions in United States dollars, Mr. Obama did not answer directly, but suggested that Iran could get access to American banking markets indirectly through European banks. The reports have drawn sharp criticism from lawmakers, including the House speaker, Paul D. Ryan, who urged the White House not to go ahead. 
  
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 Beyond that issue, Mr. Obama said Tehran could attract more American businesses by adhering not just to the letter of the nuclear deal but to its spirit, which meant not shipping missiles to the militant group Hezbollah, or otherwise destabilizing the region. 
  
 The attacks in Brussels and Paris led the president to add a session on terrorism and nuclear security. After banishing reporters and cameras from the room, he showed the leaders a video depicting a terrorist attack in a city involving a nuclear device. Afterward, the leaders discussed how they would handle such an attack. 
  
 “Fortunately, no terrorist group has yet succeeded in getting their hands on a nuclear device,” Mr. Obama told them beforehand. “Our work here will help ensure that we’re doing everything possible to prevent that.” 
  
 The meeting generated a list of announcements, including the reduction of stockpiles of highly enriched uranium in a variety of countries, including Poland and Kazakhstan, and an agreement to remove separated plutonium from Japan. The nature of these gatherings is that each nation brings along its “gifts,” or proposed offerings, and American officials say that having the leaders all show up for the summit meeting creates a forcing mechanism to get that work done. 
  
 But there are also moments that reveal behind-the-scenes disagreements, and one was evident Friday with Japan. 
  
 The energy secretary, Ernest J. Moniz, appeared with a senior Japanese official to celebrate the removal of half a ton of highly enriched uranium and separated plutonium, which was shipped to the United States. But the two men took no questions, leaving the Japanese unchallenged about the fact that they are moving ahead on a new plutonium reprocessing plant that should produce up to eight tons of plutonium each year. 
  
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 That raises concern that Japan will sit on a large supply of nuclear fuel, always a source of tension with its neighbors. Francie Israeli, an Energy Department spokeswoman, said that Japan had removed some of the most sensitive materials and that “we understand that they intend to balance any future reprocessing activities with consumption or disposition.” ||||| Play Facebook 
  
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 President Barack Obama said Donald Trump’s recent comments about nuclear weapons show the Republican presidential frontrunner doesn’t know much about -- not only foreign policy -- but "the world generally.” 
  
 At a press conference to conclude the Nuclear Security Summit on Friday, the president was asked for his reaction to Trump’s suggestion that U.S. allies Japan and South Korea manufacture their own nuclear weapons as a defense against North Korean aggression; and Trump's refusal to rule out using nuclear weapons against Europe. 
  
 Without mentioning Trump by name, Obama said the comments “tell us the person who made the statements doesn’t know much about foreign policy, or nuclear policy, or the Korean Peninsula or the world generally.” 
  
 The president said Trump’s eyebrow raising comments came up “on the sidelines” of the summit that took place in Washington, D.C. this week. 
  
 “I said before that people pay attention to American elections. What we do is really important to the rest of the world. Even in those countries that are used to a carnival atmosphere in their own politics want sobriety and clarity when it comes to U.S. elections,” Obama said. 
  
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 White House aides had previously panned the remarks, which they point out would reverse decades of bipartisan U.S. foreign policy and would increase nuclear proliferation. 
  
 Trump has argued that allowing Japan and South Korea to get the weapons would relieve the U.S. of defending their East Asia allies. Foreign leaders from both countries have dismissed the idea. 
  
 “You have so many countries already — China, Pakistan, you have so many countries, Russia — you have so many countries right now that have them,” Trump said during a CNN town hall on Tuesday. “Now, wouldn’t you rather, in a certain sense, have Japan have nuclear weapons when North Korea has nuclear weapons?” 
  
 And on Fox News this week, Trump said, "Europe is a big place. I'm not going to take cards off the table." 
  
 Obama, who has largely attempted to stay out of the 2016 presidential race, also was asked who he voted for in the Illinois Democratic presidential primary. 
  
 “It’s a secret ballot, isn’t it?” he said. |||||
A: 
At the end of the Nuclear Security Summit on Friday, President Obama took a question on the man the Economist deems a top global risk: Donald Trump. When asked about Trump's recent suggestion that Japan and South Korea get their own nuclear weapons to deal with any threat for North Korea, Obama said Trump simply doesn't know what he's talking about, the New York Times reports. The remarks "tell us the person who made the statements doesn't know much about foreign policy, or nuclear policy, or the Korean Peninsula, or the world generally," Obama told reporters at the Washington, DC summit. Leaders in the region have also dismissed the suggestion, which analysts say would go against more than 60 years of US policy. Obama said Trump's remarks came up "on the sidelines" of the summit, which focused on the threat of nuclear terrorism and was attended by dozens of world leaders, reports NBC. "I said before that people pay attention to American elections," Obama said. "What we do is really important to the rest of the world. Even in those countries that are used to a carnival atmosphere in their own politics want sobriety and clarity when it comes to US elections." Obama was also asked who he voted for in the Illinois Democratic primary. "It's a secret ballot, isn't it?" he said. (Earlier in the summit. Obama said ISIS getting its hands on a nuclear weapon "would change our world.")