Defense Secretary Ashton B. Carter gave a surprisingly upbeat assessment on Wednesday of American relations with Saudi Arabia , asserting that the kingdom welcomed the international nuclear deal reached with its regional rival, Iran . Mr. Carter, who visited Jidda and held his first meeting with King Salman, also said the Saudi monarch would visit the United States this fall and was committed to fighting the Islamic State, the Sunni militant extremist group. The defense secretary’s description of ties with the Saudis, which he made to reporters after the meeting while en route to Amman, Jordan, was unexpectedly upbeat, considering Saudi Arabia ’s strong reservations about the nuclear negotiations between the big world powers and Iran that yielded an agreement last week. Israel , another crucial American ally in the Middle East, has strongly protested the Iran accord and bluntly conveyed that message to Mr. […]