Apart from chummy chats with the Prime Minister and members of his his cabinet, Sir Leon had a range of high- profile business meetings, and even an audience with Emperor Akihito. Japanese bureaucrats were effusive in their praise of their visitor and precise in their comparisons.
Sir Leon's current visit to Tokyo, at the head of a delegation of European businessmen, is not such a glittering occasion. But the magic which made him such a hit last summer is still there. Japanese politicians, their bureaucrats and business leaders, love Sir Leon for a very simple reason: he is not American.
Tokyo's relations with the Western world are often described in terms of a triangle, with Japan, the US and Europe at its respective points.
Between the US and Japan, the line is thick, if uneven. Combined trade between the two countries came to $183bn (pounds 1.2bn) in 1995, and bilateral relations are stiffened by the US-Japan security treaty.
The fly in the ointment is Japan's perennial trade surplus. Even after the yen's rise last year dramatically raised the price of Japanese exports, Tokyo was still selling $43bn more to the US than it bought.
The Europe-Japan line is weaker. Total trade with the EU last year came to $128bn. But, superficially Tokyo's relationship with the EU has a warmth and cordiality never seen in trade talks with Washington.
The two sides have their own reasons for keeping things this way. The Europeans know that they have a huge amount of catching up to do in their dealings with East Asia, the fastest growing trade region in the world and one of the most unpredictable in terms of security and politics. The Japanese, on the other hand, hold up the EU's approach as a textbook example of the civilised, consensual way to do business, in contrast with the confrontational approach of the US.
This was illustrated at the time of Sir Leon's visit last year. The Americans, led by Mickey Kantor, now President Bill Clinton's Trade Secretary, were threatening punitive tariffs on Japanese car imports unless Tokyo agreed to specific targets for imports of US cars.
A compromise was reached at the last minute, but the EU's mild approach, persuading Japan to sign up to a European agreement on automobile regulations, was a stark contrast and a great relief to Tokyo. Hence the red carpet unrolled for Sir Leon.
For Europe, such an approach is a political necessity. As a twitchy alliance of often fractious member countries, it can never match the political and economic punch wielded by the US government. But rather than simply making the best of a bad job, officials speak of the EU approach to trade disputes, based on the multilateral arbitration of the World Trade Organisation, as something akin to an ideology.
"The days of the old US approach are numbered," Sir Leon warned in a speech in Washington in March. "We must give priority to multilateral solutions. Cosy deals between a few key players are no longer enough."
The EU's eagerness to get a share of the Asian pie produces anomalies. At the end of July, a 10-year-old US-Japan agreement on semiconductor imports will expire. The US wants its renewal. The Japanese are resisting. But the Europeans are ambiguous. They may say cosy agreements between states are anathema, but if Tokyo and Washington strike a deal, they insist on being a part of it.
Privately, European diplomats acknowledge that the US approach is useful to them.
"Because the Americans are there waving their big stick, it improves the chances of Japan helping us," says one. "If we were all non-confrontational, they'd be less likely to come to the negotiating table." Sir Leon would be the last to admit it, but Europe's Mr Nice needs America's Mr Nasty.Reuse content