CYIL 7 ȍ2016Ȏ SOME CRITICAL REFLECTIONS ON THE EXTENDED USE OF MILITARY FORCE… seemingly equated “armed attacks” with acts of aggression”, defined in the 1974 Definition… 4.3 Self-Defence The debate about the scope of a state’s right of self-defence has continued over many years, practically since the adoption of the UN Charter. 60 One important item of the discussion is the legality and legitimacy of “preemptive and “preventive” military action. The doctrine of pre-emptive self-defence is contained in the US National Strategy. 61 In view of the UK government, the right of self-defence under international law includes the right to use force where an armed attack is “imminent”. It is widely maintained that Art. 51 only recognizes the inherent right of self-defence, which can be traced back to the “Carolina” incident in 1837. British took forcible measures against Canadian rebels in US territory. In a letter from Mr. Webster to Lord Ashburton of 27 July 1842 a justification of this armed action was confined to cases in which the “necessity of that self-defence is instant, overwhelming and leaving no choice of means, and no moment for deliberation.” 62 It is argued that the UN Charter did not affect the scope of the right of self-defence existing at that time in customary international law, which included the right of use of force in anticipation of an imminent armed attack. It is asserted that while international law permits the use of force in self-defence against an imminent attack, the use of force is not allowed as a pre-emptive strike against a “threat” of military attack that is more “remote”. 63 It seems that the doctrine of “pre-emptive attack” or precisely of “pre-emptive self-defence” is quite a new development. In the time of the “Carolina” incident there was in fact no limitation on the use of military force and the right of self-defence contained another legal substance. The main legal problem of “pre-emptive self-defence” remains, however, to indentify what constitutes or represents an “imminent armed attack”. The decision in the case of self-defence will remain in the hand of an individual state or community of states (international organization). Claims of self-defence many times became the pretext for unlawful use of armed force. Art. 51 of the UN Charter does not mention a right to use military force prior to an armed attack. According to this stipulation it is possible to implement the right to self-defence only “if an armed attack occurs”. There is an extensive, long- term debate about the legality of self-defence prior to an armed attack occurring. For 60 See MRÁZEK, J. supra note 53, p. 33. 61 White House, The National Security Strategy of the United States of America; pp. 12-16, available at: http://www.state.gov/documents/organization/63562.pdf. 62 Letter from Mr. Webster to Lord Ashburton, Department of State, Washington, 6 August 1842, available at: http://avalon.law.yale.edu/19th_century/br-1842d.asp. 63 See BETHLEM, D. Self-defense against an Imminent or Actual Armed Attack by Nonstate Actors. AJIL , 2012, Vol. 106, pp. 771-712.