While Calvo has surpassed all other South Americans in the importance of his contribution to the theory of International Law, Dr. Luis Maria Drago has done the same as regards the practice. Towards the close of 1902 England, Germany, and Italy had blockaded the coast of Venezuela on account of certain grievances. On December 29, 1902, Dr. Drago, then Minister for Foreign Affairs, despatched a note to the Argentine Minister in Washington. He maintained that no European State was entitled to intervene by force in the affairs of an American nation, still less to occupy its territory, in order to recover a debt due from its Government to the subjects of the intervening State, such intervention being an infringement of the sovereignty of the debtor State and of the principle of the equality of the sovereign States.[88] This doctrine, though never precisely stated, had been foreshadowed by Calvo. It has been pointed out[89] that the blockade of 1902 was not originally instituted on account of Venezuela's failure to pay debts, but to obtain redress for outrages inflicted upon the subjects of the blockading Powers, that Venezuela had refused the suggestion of arbitration, that Dr. Drago misunderstood the Venezuelan question, and that the Powers never intended permanently to occupy any part of Venezuela. Further, Mr. Hay, in his reply to Dr. Drago, said: "The President declared in his Message to Congress, December 3, 1901, that by the Munroe Doctrine 'we do not guarantee any State against punishment if it misconducts itself, provided that punishment does not take the form of the acquisition of territory by any non-American Power.'" Although the practice, against which the Drago Doctrine protests is liable to be abused, it would hardly be prudent on the part of European Powers nor conducive to progress in backward States, if the right of collecting debts were surrendered altogether; and this view was taken at the Hague Conference of 1907. It adopted the Drago Doctrine in a modified form, providing that force must not be used for the recovery of ordinary public debts originating in contracts, but the prohibition was not to apply if the debtor State refused or ignored an offer of arbitration, obstructed the process, or repudiated the decision. The resolution was adopted by thirty-nine votes. There were five abstentions, including Venezuela, which had no liking for the modifications. This tangible addition to the public law of the world, which was one of the few successes of the Conference, was a great personal triumph for Dr. Drago, who was then the Argentine Delegate to the Conference. There have been many other meritorious Argentine writers on legal subjects of all kinds, as well as commercial and economic, but this account of two great names must suffice.