On this question British policy may change with circumstances, and British precedents may be uncertain, but the original American policy is unchangeable, and the American precedents which illustrate it are solemn treaties. The words of Vattel and the judgments of Sir William Scott were well known to the statesmen of the United States; and yet, in the face of these authorities, which have entered so largely into this debate, the National Government at an early day deliberately adopted a contrary policy, to which for half a century there was steady adherence. It was plainly declared _that only soldiers or officers could be stopped_, thus positively excluding the idea of stopping ambassadors, or emissaries of any kind, not in the military or naval service. Mr. Madison, who more than any other person shaped our national policy on Maritime Rights, has stated it on this question. In his remarkable despatch to Mr. Monroe, at London, dated January 5, 1804, he says:-- “The article renounces the claim to take from the vessels of the neutral party, on the high seas, any person whatever _not in the military service of an enemy_, an exception which we admit to come within the Law of Nations, on the subject of contraband of war. _With this exception, we consider a neutral flag on the high seas as a safeguard to those sailing under it._”[63] Then again, in the same despatch, this statesman says:-- “Great Britain must produce, then, an exception in the Law of Nations in favor of the right she contends for. But in what written and received authority will she find it? In what usage, except her own, will it be found?… But nowhere will she find an exception to this freedom of the seas, and of neutral flags, which justifies the taking away of any person, _not an enemy in military service_, found on board a neutral vessel.”[64] And once more, in the same despatch, he says:-- “Whenever a belligerent claim against persons on board a neutral vessel is referred to in treaties, _enemies in military service alone_ are excepted from the general immunity of persons in that situation; _and this exception confirms the immunity of those who are not included in it_.”[65] In pursuance of this principle, thus clearly announced and repeated, Mr. Madison instructed Mr. Monroe to propose a convention between the United States and Great Britain containing the following stipulation:-- “No person whatever shall, upon the high seas and without the jurisdiction of either party, be demanded or taken out of any ship or vessel belonging to citizens or subjects of one of the parties, by the public or private armed ships belonging to or in the service of the other, _unless such person be at the time in the military service of an enemy of such other party_.”[66]