Amid escalating threats from China in the Taiwan Strait, senators argue that the U.S. must quickly modernize its air arsenal.

China held large-scale military exercises surrounding Taiwan and its outlying islands Monday in what it called a warning against Taiwan independence. China’s Defense Ministry said the drills were a response to Taiwanese President Lai Ching-te’s refusal to concede to Beijing’s demands that Taiwan acknowledge itself as a part of the People’s Republic of China under the rule of the Communist Party.

China is holding large-scale naval and air force exercises circling Taiwan and outlying islands.