Seoul, South Korea CNN  —  The United States has approved the potential sale of 20 F-16 fighter jets to Manila, giving the key US ally in the Indo-Pacific a major upgrade to its air force just days after US Defense Secretary Pete Hegseth vowed to counter “China’s aggression.” The US Defense Security Cooperation Agency (DSCA) announced the proposed sale of the F-16s and related equipment, worth an estimated $5.58 billion, in a statement on Tuesday. “This proposed sale will support the foreign