US President Barack Obama welcomes Saudi Arabia's Crown Prince Mohammed bin Nayef and Deputy Crown Prince Mohammed bin Salman bin Abdulaziz as he plays host to leaders and delegations from the Gulf Cooperation Council countries at the White House in Washington, May 13, 2015. Jonathan Ernst/REUTERS Yesterday President Obama greeted the No. 2 and No. 3 officials of Saudi Arabia in the Oval Office.

Obviously, US-Saudi relations are not in good shape, as we learned from the refusal of King Salman to attend the Gulf summit Mr. Obama tried to call.

But the least the president might have done was to get the names right. Here is an excerpt of what he said, from the White House web page:

Remarks by President Obama and Crown Prince bin Nayef of Saudi Arabia THE PRESIDENT: Well, it’s wonderful to welcome back the Crown Prince of Saudi Arabia, Mohammed bin Nayef, as well as Deputy Crown Prince Salman. We are very pleased to have them both here today, as well as the delegation from Saudi Arabia. As all of you are aware, the United States and Saudi Arabia have an extraordinary friendship and relationship that dates back to Franklin Roosevelt and King Faisal, and we are continuing to build that relationship during a very challenging time.

First of all, the name of the deputy crown prince is not Salman; that’s his father’s name. His name is Mohammed bin Salman.

Minor detail? How about this one: In 1945, FDR met the founder of the modern Saudi kingdom, the grandfather of the two princes Obama was greeting in the Oval Office. President Obama called him King Faisal, but the founder was King Abdul Aziz ibn Saud. His son Faisal ruled from 1964 to 1975.

What must the Saudis, and other Gulf rulers, think when the president does not appear to know the name of the deputy crown prince, and does not know with whom FDR met? Bad staff work? Failure to Google? Lack of interest?

Yes, getting the names wrong is not a casus belli, but it will deepen the sense in the Gulf and the wider Middle East that the president of the United States does not know what he is doing in their region.