Loveland notes that it is difficult to extract a rule as to the circumstances under which a minister will be required to resign, and he draws on Finer's suggestion that political expediency rather than political morality may be the touchstone in explaining the scope of the modern doctrine. Political expediency appears to have played some part in the resignation of the Foreign Secretary, Lord Carrington, in 1982, following Argentina's invasion of the Falkland Islands. He had underestimated the threat from Argentina, but would not necessarily have violated any constitutional convention had he stayed in office. It subsequently became apparent that one reason for his stepping down was to assist the government.