After being echoed during the presidential campaign of former Democratic presidents John F. Kennedy and Franklin D. Roosevelt and Republican Abraham Lincoln, the president-elect should on this occasion resume Reagan's "true talk".
But the populist tribune of 70 years does not write alone. The main editor of the speech will be Stephen Miller, a young Californian former advisor to the future Justice Minister Jeff Sessions, who has already signed his speech at the Republican party convention.
In 1981, after having begun his speech by thanking his predecessor, Ronald Reagan affirmed that "the United States is confronted with an economic evil of great extent". He promised to reform the tax system and praised the merits of free enterprise - two files that will mark his eight years in power.
"In this current crisis, the state is not the solution to our problem, the state is the problem," he had hammered.
The relatives of Donald Trump indicate that he has not yet defined the main theme of his speech. But lightening the burden on companies to repair an economy that it considers to be failing should be among its priorities.
- A definition of the future president -
His spokesman Sean Spicer explained that the real estate tycoon had spent a lot of time during the holiday season discussing and rereading drafts with his main advisors.
The investiture speech marks the start of a new presidency and often defines, a posteriori, the occupants of the White House.
It was in this speech that Kennedy (1961-63) proclaimed that "the torch was passed on to a new generation of Americans", embodying the turn of the 1960s. He also invited the Americans to "ask not what That your country can do for you but what you can do for your country ", generating a sense of national service that continues to this day.
A few decades earlier, Roosevelt (1933-1945) sought to restore confidence in a country still shaken by the Great Depression by stressing that "the only thing we need to fear is fear itself."
And Lincoln (1861-1865) tried to heal the wounds of the Civil War by exhorting the Americans to consider the future "without malice towards anyone, with charity for all."
- Nixon at the convention -
Donald Trump also appealed to historian Douglas Brinkley and long-time advisors, such as right-wing extremist Steve Bannon.
Wednesday, MM. Brinkley and Trump evoked "a sort of history of the presidency and past investitures" and also spoke of the most significant presidential promises, the historian reported.
The billionaire "was very interested in the man walking on the moon and the photo of the moon, so we talked a bit about it," he added, referring to President Kennedy's promise to send a Man to this star in a speech at Rice University in Texas (south).
The text by Mr. Trump in three weeks will not only be a measure of his policy. It will also allow him to gauge his qualities as a speaker and his ability to broaden the horizon of the Americans.
But the real estate tycoon is more comfortable talking about him and rallying his supporters more extreme than to read speeches prepared in advance.
A notable exception was his inauguration speech at the Republican convention in Cleveland (North) in July. This acceptance speech was inspired by that of Richard Nixon (1969-1974) at the convention of the Republican party in 1968.
A speech without a blush - dark tide - in the United States. "When you look at America, you see cities wrapped in smoke and flames," Nixon said. "We can hear the sirens screaming in the night".
Donald Trump restored the same sense of discomfort to Cleveland forty years later, saying before the militants that the "convention was taking place at a time of crisis for our country." "Attacks on our police and terrorism in our cities threaten our way of life."
Nixon's plea for a "new leadership in America" had also become Mr. Trump's rejection of "the same politicians" who caused the problems.
"I am your voice," he said. "I'm the only one who can fix it."