One analyst says Iran's missile strike against U.S. forces in Iraq was “the smallest attack that Iran could carry out while at the same time being able to say they got revenge."

Peter Viggo Jakobsen, an associate professor with the Royal Danish Defense College, added Wednesday that Iran has "done all that is possible to avoid American casualties. If what we hear is correct, they have warned the Americans in advance."

He told Denmark’s TV2 channel the Iranians are doing all they can to avoid an American military response as harsh as President Donald Trump has promised.

"I would be deeply surprised if the Americans choose to respond militarily again,” he said.