The US military is continuing a significant buildup of air and naval assets in the Middle East as negotiations over a deal with Iran continued with talks in Geneva on Tuesday. The pieces are being moved into place both to pressure Tehran as terms of a deal are discussed and to have options to strike inside the country should negotiations over its nuclear program fail,

Indirect talks between American and Iranian officials in Switzerland ended on Tuesday with an agreement on a “set of guiding principles,” according to Iran’s foreign minister, who said both sides had ...