Mr. Biden said it was in the United States’ interest for Japan to recover and help lift the sagging global economy. “Some around the world are betting on the decline of America and the inability of Japan to recover,” Mr. Biden said at a speech at the Sendai Airport. “They are making a very bad bet.”  The airport showcases the good will created by the American military’s large relief efforts after the earthquake and tsunami, which left some 20,000 people dead or missing. American forces worked with Japanese military personnel to reopen the airport after a 10-foot surge of seawater covered the runway with mud and mangled cars and stranded more than 1,000 people in the terminal.  “I’m proud that our military was given the privilege to join your forces” in repairing the airport, Mr. Biden said in his speech.  In a meeting with the prime minister earlier in the day, Mr. Biden praised the dignity and perseverance of the Japanese people in the face of the disaster, and received Mr. Kan’s thanks for the American relief efforts.  Relations between the two countries frayed a bit last year during a dispute over an American air base on Okinawa. But on Tuesday, Mr. Biden repeatedly spoke of friendship and said he had no doubt Japan would have come to America’s aid if the tables had been turned.  Mr. Biden spent several hours in Natori, a town made famous by video clips, broadcast worldwide, of the tsunami tearing through homes and farm fields. He joined the town’s mayor in laying a bouquet of white flowers in front of a shattered home near Natori’s ravaged waterfront, and visited a community center that had served as a refugee center after the disaster.  Mr. Biden seemed relaxed, making jokes about his thinning hair and holding a young boy for several minutes in one arm as he shook hands with survivors. The Japanese applauded him and seemed genuinely touched. “I feel gratitude that he would come all the way here to support us,” said Katsuko Suzuki, 79.  At several points during the visit, Mr. Biden said Americans had been moved by the survivors’ stoicism and quiet courage.  “The American people admire the spirit of the Japanese people,” he said. “Disaster met its match in the legendary industriousness and perseverance of the Japanese people.”  The country’s governments have not persevered so well. Whoever succeeds Mr. Kan will be Japan’s sixth prime minister in five years. The new cabinet will inherit daunting challenges, including Japan’s largest reconstruction effort since World War II; radiation problems over a wide swath of the nation; a soaring yen that is battering the country’s export-led economy; an aging population; and burgeoning debts. Mr. Kan’s Democratic Party controls Parliament’s more powerful lower house, but not the upper house, leading to political gridlock on many issues.  Likely candidates to succeed Mr. Kan include a former foreign minister, Seiji Maehara; the finance minister, Yoshihiko Noda; and the trade minister, Banri Kaieda. Mr. Maehara, 49, an outspoken foreign policy hawk, is seen as a front runner, though he is still mired in a political donation scandal that forced him to resign in March.  Mr. Kan had said he would step aside after three major bills, on renewable energy, public debt and supplemental spending, were approved by Parliament. The spending bill passed in July, and the other two are likely to be passed by the end of the month.  A version of this article appears in print on August 24, 2011, on Page A12 of the New York edition with the headline: In Visit to Japan, Biden Seeks to Inspire Recovery. Order Reprints| Today's Paper|Subscribe
On the final leg of an eight-day Asian trip, Vice President Joseph R. Biden Jr. spoke in a town ravaged by the tsunami in March.