NEW DELHI—China is building 120 new silos for intercontinental ballistic missiles (ICBM) near its northwestern desert city of Yumen, indicating a significant expansion in its nuclear forces and sparking concerns of a Taiwan-related conflict between China and the United States. Construction of these silos began in March 2020, with major assembly happening rapidly after February 2021, and is likely meant for China’s DF-41 ICBM, which is capable of carrying multiple warheads, according to a satellite imagery analysis by the James Martin Center for Nonproliferation Studies at the Middlebury Institute of International Studies at Monterey (CNS/MIIS). “If the silos under construction at other sites across China are added to the count, the total comes to 144 silos under construction,” said Jeffrey Lewis, director of the East Asia Nonproliferation Program at the CNS/MIIS in a summary of the analysis on his blog, Arms Control Wonk. “We believe China is expanding its nuclear forces in part to …