Lt. General Joseph Guastella, commander of the US Air Forces Central Command, cited Iran's claim "categorically wrong," adding that "the plane was over the Strait of Hormuz and fell into international waters."
The Pentagon published a map that states exactly where it is said the plane was shot down.
Why is it important if the drone was shot down in international airspace compared to Iranian territory?
Claiming that the US plane not only violated sovereign airspace but also "spy and information gathering", Iran is likely to try to legally justify its self-defense response as a transition between sending a message to Washington while the odds are limited by military retaliation.
"The Iranians are clearly trying to prove their ability to defend themselves and prevent further American action, and they probably thought that by targeting a drone they could send this message with minimal risk," the CNN said -Military analyst John Kirby. a retired Navy Rear Admiral.
A high-ranking Iranian security official seemed to point out that this warned the case later on Thursday by warning foreign planes against aggression into his airspace.
"Iran Defending all of his sea, land and air borders and his airspace aggression is his "redline", "said Iranian Supreme National Security Council secretary Ali Shamkhani, according to state IRNA news coverage.
The Iranians Could Yet Have Did It Kirby said the launching of the drone in international airspace could now give the Trump administration reasons to ask for more support from the international community for reprisals and to weaken European restraint to the Iranian economy continue to support. "
According to the Manual of the Navy to the Law on Marine Operations, an enemy action is defined as" an attack or other use of force against the United States, US forces or other designated persons or assets; it also includes • violence used directly to exclude or obstruct the mission and / or duties of US forces. "
" I think the Trump administration could – if it wishes – implement the principle of self-defense in the UN Charter and in the operations accordingly, "said Kirby." But these operations would have to be proportional to the threat – one Threat that has now become even more difficult due to the sophistication of Iranian air defense. "
" Any airspace within the reach of Iranian systems must now be considered controversial. Without a major US escalation to suppress Iranian air defenses, this will certainly limit US military options, "he added.
Strategic significance of the Strait of Hormuz
The Pentagon's claim that the The US drone shot down over the Strait of Hormuz is also an important detail in the broader context of escalating tensions in the region in which Iran is involved.
There is no place in the world more important for global oil supply as the Strait of Hormuz, and the US has vowed to never allow Iran to prevent its passage through the waterway.
The channel, which is only 34 km wide at its narrowest point, is the only possibility of oil from the Persian Gulf into the oceans, so the attack is on two ships, one carrying oil and the other a cargo C transported in the nearby Gulf of Oman so worrying.
If the road were closed because of imminent permanent closure attacks, it would be a severe blow to the world economy. The price of oil, which had recently dropped, rose 4% after Thursday's attack.
The Strait of Hormuz, which connects the Gulf of Oman and the Persian Gulf , "is the world's most important choke point," said the US Energy Information Board.
President Donald Trump left the door open for a possible military strike against Iran in response to the crash of an American drone Thursday morning in a threatening manner, saying "Iran made a very big mistake!"
Trump, however, pursued this tweet by saying that he believes Iran has mistakenly shot down the US drone and finds it "hard to believe it was intended".
"Iran has probably made a mistake, I imagine it was a general or someone who made a mistake when shooting down this drone," he told reporters in the Oval Office.
Even so, many analysts strongly suspect that outspoken Iran hawks such as Republican Sens Tom Cotton of Arkansas and Lindsey Graham of South Carolina are trying to get Trump into a position where a military confrontation without an Iranian is inevitable becomes a surrender that seems highly unlikely.
And it remains to be seen how the Trump administration will react.
"I do not expect this latest incident to lead to complete conflict on its own, but it is certainly escalating and, regrettably, could further restrict the already small amount of leeway Trump has given himself," Kirby said.
Ryan Browne, CNN's Stephen Collinson and Frederik Pleitgen have objected to this report.