America's seldom expressed but widely shared antagonism toward Europe's monarchical governments broke loose at the first news of the revolutions that, beginning in France during February 1848, swept rapidly across Germany and the whole continent. The U.S. minister in Paris recognized France's provisional government. Senator Edward Hannegan of Indiana reported a joint resolution from the Committee on Foreign Relations that offered the country's congratulations to the people of France. The absence of any obligations to France assured the resolution's overwhelming approval.
By 1849, the spontaneous uprising of one European people after another diverted attention from France to Hungary, where the Magyar patriots were engaged in a heroic struggle against Austrian rule. That summer, while the American people applauded the successive Hungarian triumphs, Secretary of State John M. Clayton dispatched Ambrose Dudley Mann as a special agent to report on the progress of the revolution and offer the nation's encouragement. After winning momentary success under their eloquent leader, Lajos Kossuth, the Hungarians suffered disaster at the hands of Russian troops brought to the aid of the Austrian emperor. Early in 1850 Cass proposed a resolution demanding that the administration sever diplomatic relations with Austria. Clay, a realist since his stint as secretary of state under John Quincy Adams, turned his ridicule on Cass's proposal. There was, he told the Senate on 7 January, no relationship between the Michigan senator's premises and his conclusions. His resolution offered nothing to the Hungarians. Why, Clay asked, single out Austria? Hungary lost its independence struggle to Russian, not Austrian, forces. The country's very greatness, Clay cautioned, "draws after it great responsibilities…to avoid unnecessary wars, maintaining our own rights with firmness, but invading the rights of no others." The Senate tabled Cass's resolution.
Meanwhile, the exiled Kossuth languished under detention in Turkey. But in September 1851, Webster, now secretary of state, with the cooperation of U.S. minister George Perkins Marsh, secured the release of Kossuth and fifty of his Magyar associates. Congress passed a resolution inviting Kossuth to visit the United States, while the president dispatched the USS Mississippi, already in the Mediterranean, to carry him to England. After a triumphal stop in England, he proceeded to the United States. Upon his arrival in New York City on 5 December, announced by the booming of cannon, Kossuth received the city's greatest ovation since the visit of Lafayette a quarter century earlier. New York experienced a Magyar-mania epidemic. Soon the Kossuth craze spread from the Atlantic to the Great Lakes. American orators used the occasion of his presence to express sympathy for the oppressed of Europe. Whigs—largely realists—were not amused; they resented both the cleverness of Kossuth's appeal to the country's idealist sentiment, as well as the approval his words apparently received. What troubled Kossuth's realist critics especially was his open quest for diplomatic, economic, and even military assistance to rekindle the Hungarian independence movement. For them, such appeals exceeded the bounds of acceptable international behavior.
Congress voted to invite Kossuth to Washington, D.C. The Hungarian accepted with alacrity; the success of his mission in America hinged on his acceptance by an administration that was determined to offer him nothing. On 23 December, Webster acknowledged privately the need for caution in dealing with Kossuth: "We shall treat him with respect, but shall give him no encouragement that the established policy of the country will be in any degree departed from." Two days later, Webster admitted that Kossuth's presence in Washington would be embarrassing. Upon Kossuth's arrival, Webster privately outlined his course of action: "I shall treat him with all personal and individual respect, but if he should speak to me of the policy of 'intervention,' I shall 'have ears more deaf than adders.'" At the White House on 31 December, Kossuth, despite Webster's request, could not resist the temptation to make a lengthy plea for American aid. President Millard Fillmore reminded the Hungarian leader that U.S. policy on intervention had been uniform since the Republic's founding. At subsequent dinners hosted by the Websters and the president, Kossuth's scarcely concealed anger embarrassed all who attended.
At a congressional banquet in Kossuth's honor, Webster expressed his hope to see the American model established upon the Lower Danube. He toasted Hungarian independence but refused to offer what Kossuth needed: something tangible for the Hungarian cause. On 9 January 1852, Clay received Kossuth in his chamber. Clay assured the Hungarian leader that the United States could not transport men and arms to eastern Europe in sufficient quantity to be effective against Russia and Austria. Such an attempt, he added, would depart from the country's historic policy of nonintervention. "Far better is it for ourselves, for Hungary, and for the cause of liberty," Clay concluded, "that, adhering to our wise, pacific system…, we should keep our lamp burning brightly on this western shore as a light to all nations, than to hazard its utter extinction amid the ruins of fallen and falling republics in Europe." Kossuth soon returned to Europe, suffering the disillusionment of those who expect too much of sentiment.