The policy which the Secretary of State was known to favor was that of coercing England through restrictions upon trade. The implications of this policy were suggested by his often-quoted remark touching upon the dependence of British manufacturers: "There are three hundred thousand souls who live by our custom: let them be driven to poverty and despair, and what will be the consequences?" He lost no opportunity to urge upon his party associates the need of passing retaliatory legislation against Great Britain. It was well known, of course, that the President would support any fair application of his theory of peaceable coercion.

At first there was a general disposition to try the effect of an embargo; but more prudent counsels prevailed when the news of Trafalgar reached America. Congress finally adopted, in April, 1806, a non-importation bill, which was to become effective eight months later. There was some point to Randolph's criticism when he declared it to be "a milk-and-water Bill. A dose of chicken broth to be taken nine months hence"; for the act prohibited only the importation of such English goods as could be manufactured in the United States or procured elsewhere. Such a measure was not likely to make the manufacturers of England quail. In the mean time, the Administration was to accomplish what it might by direct negotiation with the British Ministry, using this Nicholson Act as a covert threat. Much against his will, Jefferson had to nominate another envoy to act with Monroe. His choice fell upon William Pinkney, of Maryland. The friends of Madison were not unwilling to humiliate Monroe, whose presidential aspirations might interfere with Madison's succession, for Jefferson had let it be known as early as the summer of 1805 that he did not seek a reëlection.

A few days after Congress adjourned occurred the Leander episode. This frigate was one of several British war vessels whose presence in American waters was a constant menace to merchantmen and an insult to the National Government. From time to time they appeared off Sandy Hook, lying in wait for American vessels which were suspected of carrying British seamen who had fled from the hard conditions of service on ships of war. An American merchantman was likely at any time to be stopped by a shot across her bow and to be subjected to the humiliation of a visit from a search crew. On April 25, 1806, the Leander, in rounding up a merchantman, fired a shot which killed the helmsman of a passing coasting sloop. The incident or accident threatened to assume the proportions of a casus belli.

The practice of impressment was an old grievance which seemed to Americans devoid of any justification. From the British point of view there was much to be said in extenuation of the practice. It should not be forgotten that Great Britain was locked in a life-and-death struggle with a mighty antagonist, and that she had need of every able seaman. Owing to the rigorous life on board of men-of-war, every ship's crew was likely to be depleted by desertions whenever she touched at an American port. Jack Tar found life much more agreeable on an American merchantman; and he rarely failed to procure the needful naturalization papers or certificates which would give him a claim to American citizenship. The right of expatriation was not at this time conceded by the British Government. Once an Englishman, always an Englishman. Surely, then, British commanders might claim their own seamen on the high seas. Officially, at least, they never claimed the right to impress American seamen. Yet where differences of speech were so slight, the provocation so strong, and the needs of the navy so great, search crews were not always careful to distinguish between Britishers and Yankees.

The United States never admitted the justice of these claims. To concede the right of search on the high seas was to admit a vast extension of British jurisdiction. As early as 1792, Jefferson had stated the principle for which the United States had consistently contended: "The simplest rule will be that the vessel being American shall be evidence that the seamen on board of her are such." The principle was never accepted by any British ministry. The practice of impressment continued to harass each succeeding administration. In 1806, a crisis seemed at hand. Madison reported to the House of Representatives the names of nine hundred and thirteen persons who appeared to have been impressed from American vessels. How many of these were British deserters under American names, it is impossible to say. The number reported by Madison is at least an index to the sense of injury which the nation felt.

When President Jefferson sent Pinkney to join Monroe in securing a comprehensive treaty with Great Britain, which should restore West India trade to its old condition and provide indemnity for the American vessels condemned in the admiralty courts, he set down, as a sine qua non in his instructions, the renunciation by the British Government of the practice of impressment. It was an ultimatum which expressed a truly national feeling; but with the consciousness of power which the domination of the high seas gave, the British commissioners treated this ultimatum, somewhat contemptuously, as an impossible and unwarranted demand. The American mission should have ended then and there; but on obtaining assurances that greater care would be exercised in impressing seamen, Monroe and Pinkney determined to disregard their instructions. Negotiations were continued and culminated in a treaty, December 1, 1806, which ran counter to the injunctions of the President in every particular. He refused to submit the document to the Senate. Nevertheless, he permitted Madison to draft new instructions for the commissioners, in the hope that the treaty could be made a basis for further negotiations. While these new instructions were crossing the ocean, a disaster occurred which brought the United States and Great Britain to the verge of war.

In the early months of 1807, some French frigates had run up Chesapeake Bay to escape a British squadron. Relying on what Jefferson pleasantly termed the hospitality of the United States, these British men-of-war dropped anchor in Lynnhaven Bay, near Cape Henry, where they could watch the passage through the capes. From one of these British vessels a boat crew of common seamen made their escape to Norfolk. Just at this time the new frigate Chesapeake, which had been partially fitted out at the navy yard at Washington for service in the Mediterranean, dropped down to Hampton Roads to receive her complement of guns and provisions for a three years' cruise.

On June 22, the Chesapeake passed out through the capes, preceded by the Leopard, a British frigate of fifty guns. When they were well out on the high seas, the Leopard drew alongside the Chesapeake and signaled that she had a message for Commodore Barron. This message proved to be an order from Admiral Berkeley at Halifax, instructing commanders of British vessels who fell in with the Chesapeake to search her for deserters. The American commander denied that he had deserters on board and refused to allow the search. Almost immediately the Leopard approached with her gundecks cleared for action. Unaware of his danger Commodore Barron had not called his crew to quarters. The Leopard opened fire and poured three broadsides into the helpless American vessel, killing three men and wounding eighteen others. After fifteen minutes Barron hauled down his flag to spare his crew from needless sacrifice, and suffered the British commander to search the dismantled Chesapeake. Four alleged deserters were found and taken away, three of whom subsequently were proved to be American citizens. The Leopard then returned to the squadron off Cape Henry, while the Chesapeake limped back to Hampton Roads.