The first clear signs that Gordon Brown will reorder Britain's foreign policy emerged last night when one of his closest cabinet allies urged the US to change its priorities and said a country's strength should no longer be measured by its destructive military power. Douglas Alexander, the trade and development secretary, made his remarks in a speech in America, the first by a cabinet minister abroad since Mr Brown took power a fortnight ago. The speech represents a call for the US to rethink its foreign policy, and recognise the virtues of so-called "soft power" and acting through international institutions including the United Nations.