China's patience with North Korea is wearing thin, and a widely-expected nuclear test by the latter could bring that frustration to a head. China signaled its growing unhappiness by agreeing to tightened UN sanctions after NKorea launched a rocket in December, which prompted harsh criticism from the international community. Perhaps Kim Jong-un thinks Xi Jinping would indulge him. Although China welcomed Kim Jong-un's ascension after his father died and maintained flows of aid and investment, Kim has ignored China's interests in a stable neighborhood with his two rocket launches and nuclear test plan. North Korea announced last month it would conduct a test to protest the toughened UN sanctions. Many Chinese believe that the North Koreans are taking Chinese aid for granted. If North Korea is no longer beneficial to China, China may even break the alliance with North Korea and work closer with the US to deter North Korean provocations.