THE stressful and tumultuous days that followed the formal entry of the United States into the World War in April, 1917, and the scarcely less critical ones that have succeeded --measuring little more than the years of a human being's development from birth to maturity -- have witnessed the most unbridled professions of isolationism and the most strenuous and far-reaching actual participation in world affairs that the American people have ever known. It goes without saying that international acts have proportionately accompanied the latter development; executive agreements to the number of some 730 have much more than doubled the list as it stood at the beginning of this last and shortest of the periods of time into which, for convenience, these instruments have been distributed for purposes of the present discussion.
It will be difficult to mention, in the straitly limited pages which follow, all the groups, even, into which so many international acts may appropriately be classified. A reasonable picture of the whole may probably be had, nevertheless, from treatment of those that are of especial significance or interest in some ten categories representative of outstanding historical events or developments. Apart from these, the miscellany of twenty years' agreement making includes abundant repetition of agreements on subjects already familiar,1 but often assuming a distinctively modern guise, as well as subjects which seldom if ever appeared in the earlier period. Among the latter a random choice includes multipartite or bipartite acts relating to tourists' automobiles,2 statistics of causes of death3 (juxtaposition unpremeditated), exchange of information regarding the traffic in narcotic drugs,4 diplomatic____________________