Madison convinced Jefferson to refrain from proposing the amendment, and the administration ultimately submitted the Louisiana Purchase Treaty for approval by the Senate, without an accompanying constitutional amendment.[146] Unlike Jefferson, Madison was not seriously concerned with the constitutionality of the purchase. He believed that the circumstances did not warrant a strict interpretation of the Constitution, because the expansion was in the country's best interest.[147] The Senate quickly ratified the treaty, and the House, with equal alacrity, passed enabling legislation.[148][149][150]
Early in his tenure, Jefferson was able to maintain cordial relations with both France and Britain, but relations with Britain deteriorated after 1805.[151] The British ended their policy of tolerance towards American shipping and began seizing American goods headed for French ports.[152] They also impressed American sailors, some of whom had originally defected from the British navy, but some of whom had never been British subjects.[153] In response to the attacks, Congress passed the Non-importation Act, which restricted many, but not all, British imports.[152] Tensions with Britain were heightened due to the Chesapeake–Leopard affair, a June 1807 naval confrontation between American and British naval forces, while the French also began attacking American shipping.