Japanese Prime Minister Sanae Takaichi will likely be able to make sufficient concessions to U.S. President Donald Trump during their summit to avoid U.S. retaliation and/or a slowdown in her own military modernization policies, but a protracted Iran war could nonetheless undermine her economic growth plans. Takaichi will visit Washington on March 19 to meet with Trump for the first time since she was reappointed as premier on Feb. 18, aiming to firm up relations with Japan's top defense ally and second-largest trade partner. Until recently, the meeting was expected to focus on implementing their July trade deal, cooperating on energy and technology supply chains and coordinating military modernization efforts to jointly deter Chinese aggression against Taiwan. On March 14 and 15, however, a more fraught issue was added to the list when Trump demanded that U.S. allies and partners like Japan, South Korea and the United Kingdom assist the...