Five Things to Know, April 10, 2023

1.   A U.S. Navy warship on Monday cruised near a chain of islands claimed by China, Taiwan and other countries, coinciding with the third day of Chinese exercises around Taiwan in the wake of meetings between Taiwan’s president and U.S. officials. The guided-missile destroyer USS Milius conducted a freedom-of-navigation operation near Mischief Reef in the Spratly Islands, a group of about 100 islands between Vietnam and the Philippines, to uphold the “rights, freedoms and lawful uses of the sea,” the U.S. 7th Fleet said in a Monday email.

2.   China’s military declared Monday it is “ready to fight” after completing three days of large-scale combat exercises around Taiwan that simulated sealing off the island in response to the Taiwanese president’s trip to the U.S. last week. The “combat readiness patrols” named Joint Sword were meant as a warning to self-governing Taiwan, which China claims as its own, China’s military said earlier.

3.   Seoul intends to discuss with Washington the leak to social media of purported U.S. military files, some of which reportedly contained details of sensitive discussions between senior South Korean officials, President Yoon Suk Yeol’s office said Monday. “This process would be done based on the trust relationship formed through the [South Korea]-U.S. alliance,” Yoon’s presidential office said in a statement Monday.

4. Dozens of leaked Defense Department classified documents posted online reveal details of U.S. spying on Russia’s war machine in Ukraine and secret assessments of Ukraine’s combat power, as well as intelligence gathering on America’s allies, including South Korea and Israel. NBC News obtained more than 50 of the leaked documents, many of them labeled “Top Secret,” the highest level of classification. 

5.   North Korea on Saturday claimed it tested this week a second known type of nuclear-capable underwater attack drone designed to destroy naval vessels and ports, adding to a flurry of weapons demonstrations this year that have heightened tensions with rivals.