In its length, scope and diplomatic implications, this two-part broadcast on the US Cable News Network (CNN) was without precedent. The elected leader of one of the most conservative regimes in the world bypassed conventional channels of diplomacy and used the 20th-century medium of communications to appeal directly to the American public.
For a leader regarded as a relative moderate, whose authority is believed to face constant challenge from more conservative ayatollahs, Mr Khatami came within a hair's breadth of condemning the siege of the US embassy during the Islamic revolution in 1979 - the event that so stamped itself on the American psyche. He condemned outright the regular burning of US flags on Iranian streets as something he would like to stop - going out of his way to associate Iran's "supreme leader", the more conservative Ayatollah Ali Khamenei, with that view.
The broadcast's format, like many of Mr Khatami's sentiments, suggested elements of compromise. He began with a discourse on what he saw as the natural affinity between the people of the US and Iran in terms of their love of religion and liberty, before answering questions from CNN's senior international correspondent, Christiane Amanpour.
That he agreed to be interviewed by a woman correspondent also sent a message of its own, to America and Iran, that the hints of relative liberalism detected in his election programme were for real.
The limits to his authority were evident not only in his forceful attacks on US leaders and American diplomacy - going back to its support for the coup against Mossadegh in 1953 - but also in the modesty of his proposal for dialogue. The time was not yet ripe, he indicated, for formal talks. Rather, there should be cultural contacts, between scholars, journalists and others.
The broadcast came three weeks after Mr Khatami first intimated publicly at an opening towards the US. At the conference of Islamic countries in Tehran last month he suggested a "thoughtful dialogue" between Iran and "the great people and nation of America".
If he had hoped for an immediately positive response from Washington from last night's broadcast, he may have been disappointed. In its first reaction, within minutes of the end of the broadcast, the State Department repeated its call for "deeds, not words".
Presenting the US as keener on direct dialogue at national level than Mr Khatami appeared to be - at least in the first instance - officials said: "The way to address issues is for our two governments to talk directly." The US distrusts informal diplomacy between MPs or scholars of the sort that Mr Khatami proposed.
Analysts believe that behind the scenes Mr Khatami's interview, and in particular his demand that "there must first be a crack in this wall of mistrust", would be studied with care.
White House officials and advisers have recently been debating the extent to which Mr Khatami wields power and the merits of improving relations. Signals from Iran have also been mixed, with senior ayatollahs going on the record to deny any desire for rapprochement with the US.
Washington has, none the less, compelling reasons to be interested in better relations. Moving away from outright hostility towards Tehran could give it another avenue for exerting pressure on Iraq and containing the Taliban leadership of Afghanistan. Iran could be co-opted to play a positive role in supporting Bosnia's Muslims, so balancing Serbian influence. Improved relations also offer the US the chance of a gracious retreat from the Helms-Burton legislation as it applies to Iran. At present, third countries that trade with Iran are threatened with US sanctions. The law has damaged US diplomacy.Reuse content