He presumed unilateral authority to call on the states to prepare 100,000 militia and ordered the purchase of arms, ammunition, and supplies, writing, "The laws of necessity, of self-preservation, of saving our country when in danger, are of higher obligation [than strict observance of written laws]". The USS Revenge was dispatched to demand an explanation from the British government; it also was fired upon. Jefferson called for a special session of Congress in October to enact an embargo or alternatively to consider war.[254]

Embargo (1807–1809)
Further information: Embargo Act of 1807
In December 1807, news arrived that Napoleon had extended the Berlin Decree, globally banning British imports. In Britain, King George III ordered redoubling efforts at impressment, including American sailors. But the war fever of the summer faded; Congress had no appetite to prepare the U.S. for war. Jefferson asked for and received the Embargo Act, an alternative that allowed the U.S. more time to build up defensive works, militias, and naval forces. Later historians have seen the irony in Jefferson's assertion of such federal power. 