The name of the country is "Qatar" and its leader is referred to as the Prime Minister rather than the president. The current Qatari Prime Minister is Hamad bin Jassim bin Jaber bin Muhammad Al Thani, and you would address him as "your excellency."
"Mr. President" is the proper address for the US President. "Mr. Obama" would probably not offend him.
Mr. President.
how would u address a letter to the president of the u.s
Quatar
Islam
15
To address a former president you do not say mr. president or anything having to do with president. <---- This is WRONG. You address any former president as Mr. President. That is a title they have as long as they are alive.
President Bush -- It is customary to address ex-presidents as "president". You surely would not want to address him as just George Bush unless he is a personal friend. Governor Bush or even Mr. Bush would probably do.
mail address/president of France
Never
In newspapers, the President of the United States should be addressed as "President [Last Name]." For example, "President Biden" would be the proper way to address the current U.S. President, Joe Biden.
You would do it like this: Dear President Obama: