In fact during this silly Malvinas conflict the US took a mediating stance at best.
Apart from supplying 100 of the latest version of the Sidewinder missile to the Task Force before the US Air Force was issued any?.
Laser Target Indicators for the SAS and SBS.
1.5 million gal. of aviation fuel to the airbase at Ascension Island. KC-135 aerial tankers available to the RAF in Europe to cover RAF Tankers transfer to Ascension.
Anti Submarine Sonobuoys
US Air Force flying aggressor exercises with the Harriers on the way down the Atlantic to sharpen up their Air to Air skills against dissimilar aircraft?.
Or even passing intercepted signals and other intelligence to the task force commander?
Casper Weinberger offered the use of an American aircraft carrier in the event that one of the British carriers was lost.
Reagans UN Ambassador Jeanne Kirkpatrick viewed the anticommunist Argentine government as a potential ally in the struggle to resist the spread of Marxism in Latin America, she was guest of honor at a dinner held by Argentine's ambassador to Washington on the day the Argentinians landed in the Falklands. For a while Argentina's foreign minister, Nicanor Costa Mendez, considered invoking the Treaty of Rio de Janeiro, which would challenge the U.S. to honor its 1947 pledge to come to the aid of his country in the event of war. But Reagan allied the U.S. with Britain, leveling economic sanctions against Argentina and offering military supplies to the British.
Weinberger and Reagan were later awarded the British honour of Knight Commander of the British Empire (KBE).