U.S. defense officials have revealed that Iran threatened to shoot down two U.S. Navy aircraft flying over international waters last weekend.

CNN reports the two reconnaissance planes, an EP-3 and a P-8, were “near Iranian airspace” but within international space, just inside the Strait of Hormuz. Fortunately, the Navy crews knew they were outside the range of Iranian anti-aircraft weapons.

All three radio calls Iran made to the Navy planes used “threatening language,” according to the defense official, essentially telling the Americans they would be shot down if they ventured into Iranian airspace. The Navy crews “responded in an appropriate and calm manner.”

According to Fox News, that response did not include changing course, as the Iranians demanded. “We wanted to test the Iranian reaction,” a U.S. official explained. “It’s one thing to tell someone to get off your lawn, but we weren’t on their lawn. Anytime you threaten to shoot someone down, it’s not considered professional.”

It is also not considered very gracious if you just broke your own laws to give $1.7 billion in cash to the people threatening to shoot you for coming close to their lawn.

Fox News notes the P-8 has a crew of nine, while the EP-3 flies with roughly 24 aboard, putting about 33 American lives at risk in the incident.

CNN adds an interesting note that “senior US military officials are trying to assess whether the number of incidents with the Iranians have increased or whether more incidents are simply being reported by US naval commanders in the region because of the sensitivity to Iranian incidents.”

Were they instructed to take Iran’s taunting about American military personnel “exaggerating” these incidents seriously for diplomatic reasons?

The Iranians, meanwhile, have just launched a new 55-meter ship capable of carrying a crew of one hundred, plus a helicopter. They were evasive about whether the ship is armed but very clear about who the weapons will be pointed at if it has them.

“This ship increases the deterrent power of Iran and will have an effect on the calculations of the enemy, particularly America,” boasted the head of the Iranian Revolutionary Guard’s navy, Rear Admiral Ali Fadavi, as quoted by Reuters.

Reuters notes the ship was decorated with a banner reading, “America should go to the Bay of Pigs, the Persian Gulf is our house.”

If it’s packing surface-to-air missiles, the next Iranian threat against American aircraft might be considerably more plausible.