As the president planned the nation's escape from the troublesome issue of slavery expansion, the spread of revolution across Europe following the overthrow of the French monarchy in February 1848 captured the American imagination. The outpouring of sympathy centered on Hungary, where the Magyar patriots, under Lajos Kossuth, were struggling against Austria. In June 1849, after the Hungarians had won a succession of victories, Secretary of State Clayton dispatched Ambrose Dudley Mann, then in Germany, to Hungary to report on the progress of the revolution and offer America's encouragement. Crittenden was delighted. He wrote to Clayton,
Your readiness to recognize Hungary is a forward and bold step. I like it for the sentiment and resolution it implies. Go ahead!—it is glorious and will please our people to see the Majesty of our Republic exhibiting itself on all proper occasions, with its dignity and fearless front, in the eyes and to the teeth of misruling kings, or despots of whatever make or title they may be.
Such sentiments reflected the deep American animosity toward European repression, but the genuine interests of the United States in European politics lay in the balance of power, not in the self-determination of European peoples. Predictably the Taylor administration remained officially silent when Russian troops, coming to the aid of Austria, crushed the Hungarian uprising. Early in 1850, Cass proposed a resolution demanding that the administration sever diplomatic relations with Austria. Clayton, supported by Clay and other traditionalists, ignored Cass's overture to American sentimentalism.
For the Taylor administration the region of immediate concern was Central America. During 1849, thousands of Americans poured across Panama and Nicaragua, traveling largely along two possible canal routes en route to California. Clearly the American interest, then or later, demanded the right to build a canal and control it. As early as June 1848, the Senate approved a treaty with New Granada (now Colombia) that granted the United States transit rights across the Isthmus of Panama. In return, the United States pledged to guarantee the neutrality of the route. The British possessed British Honduras and asserted a protectorate over the Indians of the Mosquito Coast. To offset the American treaty with New Granada, the British seized control of the port of San Juan del Norte, which commanded the entrance to the best canal route across Nicaragua; they renamed the port Greytown. Then, in October 1849, the British seized Tigre Island, near the possible western terminus of the Nicaraguan route. Despite Britain's prompt release of Tigre Island, the British and the Americans were clearly on a collision course in Central America.
Clayton moved to resolve the burgeoning contest by opening negotiations with the able Sir Henry Lytton Bulwer, who reached Washington in late 1849. Neither the United States nor Britain would permit the other to have sole control of an isthmian canal. Both nations, moreover, feared that the other would attempt to strengthen its position in Central America by seizing territory. The Clayton-Bulwer Treaty, signed on 19 April 1850, resolved the canal issue by asserting that neither country, should it build a canal, had the right to fortify it or exercise exclusive control over it. The territorial arrangements were more ambiguous. Both governments agreed never to occupy, fortify, or exercise any dominion over any part of Central America; neither would they assume any protectorate over a Central American government. Clayton agreed that these limitations did not apply to areas already under British control.
For Whigs and conservatives the self-denying aspects of the treaty served the immediate interests of the United States admirably. Britain, the world's leading maritime power, had agreed not to monopolize a Nicaraguan canal or to extend its holdings along the Caribbean. Expansionist Democrats such as Cass and Douglas condemned the acceptance of the self-denying clauses as an act of national cowardice. Buchanan charged that Clayton, like Bulwer, merited a British peerage. To its partisan critics the Taylor administration had not answered the challenges either of revolutionary Europe or of British ambitions in the Caribbean.