U.S. Defense Secretary Robert Gates says North Korea will pose a direct threat to the United States within five years if the communist dictatorship isn't reined in. Gates cited the North's development of intercontinental ballistic missiles and its efforts to expand its nuclear weapons capability during a press conference in Beijing with Chinese President Hu Jintao. The Pentagon chief also noted that South Korea's tolerance for the North's behavior has "worn thin." He said it's time for Pyongyang to demonstrate specific ways it is ready to re-engage with its neighbors, such as moratoriums on missile testing and nuclear testing. Gates said China has played a helpful role in lessening tensions, and said North Korea will be a significant topic when President Barack Obama meets with Hu in Washington next week.