President Trump's last-minute decision to pull back from a retaliatory strike on Iran underscored the absence of appealing options available to him as Tehran races toward its next big challenge to the United States: building up and further enriching its stockpile of nuclear fuel. Two weeks of flare-ups over the attacks on oil tankers and the downing of an American surveillance drone, administration officials said, have overshadowed a larger, more complex and fast-intensifying showdown over containing Iran's nuclear program. In meetings in the White House Situation Room in recent days, Secretary of State Mike Pompeo contended that the potential for Iran to move closer to being able to build a nuclear weapon was the primary threat from Tehran, one participant said, a position echoed by Mr. Trump on Twitter on Friday. Left unsaid was that Iran's moves to bolster its nuclear fuel program stemmed in substantial part from the president's decision last year to pull out of the 2015 international accord, while insisting that Tehran abide by the strict limits that agreement imposed on its nuclear activities. Mr. Trump has long asserted that the deal would eventually let Iran restart its nuclear program and did too little to curb its support for terrorism.

Seated on the floor of a villa in northeast Tehran around a tablecloth spread with platters of saffron chicken and rice with barberries, about 30 officials of Iran's Islamic Revolutionary Guards Corps and guests gathered Thursday night for a prayerful celebration. "A special blessing for the commander who ordered the attack on the American drone and for the fighters who carried it out," a preacher declared, as recalled by one of the guests present, who said a raucous chorus of "amen" arose from the room. Their success earlier that day at shooting down an unmanned American Global Hawk surveillance drone (list price $131 million) surprised even some leaders of the Revolutionary Guards. They had wondered themselves whether they could hit an American target so high in the sky, according to the guest. In fact, the Revolutionary Guards sought to take out the drone in large part to prove they could do it, according to that guest and four other Iranians, including two senior current members.

WASHINGTON - U.S. military cyberforces launched a strike against Iranian military computer systems on Thursday as President Donald Trump backed away from plans for a more conventional military strike in response to Iran's downing of a U.S. surveillance drone, U.S. officials said Saturday. Two officials told The Associated Press that the strikes were conducted with approval from Trump. A third official confirmed the broad outlines of the strike. All spoke on condition of anonymity because they were not authorized to speak publicly about the operation. The cyberattacks -- a contingency plan developed over weeks amid escalating tensions -- disabled Iranian computer systems that controlled its rocket and missile launchers, the officials said.

Gur Kimchi, vice president of Prime Air, talks about Amazon's drone delivery service. Federal officials recently approved a patent for the company to explore allowing its drones to provide "home surveillance" for its customers. Gur Kimchi, vice president of Prime Air, talks about Amazon's drone delivery service. Federal officials recently approved a patent for the company to explore allowing its drones to provide "home surveillance" for its customers. Going on vacation and want some extra security around your home?

Whether it is the Irish backstop or English Channel, the issue of how the UK and Europe are controlling their borders has been thrust into the public consciousness. And as with many of the globe's conundrums, countries and private companies are turning to ever more futuristic, and often controversial, technologies in order to protect their borders. There are, of course, immediate issues for Britain's borders with quandaries such as the potential hard border in Northern Ireland following Brexit, with the nebulous'technology' promised by some politicians either still being developed or put under question. One such future proposal is a satellite system that registered mobile phones as they pass the border, while sensors buried in the ground or radars on flying drones could detect possible unlawful breaches of the boundaries. But that would still leave the question of invasive, even if largely invisible, checks that run against the Good Friday Agreement.

Several international airlines were diverting planes from flying over the Strait of Hormuz and parts of Iran on Friday, a day after the Iranian military shot down an American surveillance drone and the United States went to the brink of launching a retaliatory strike. The Federal Aviation Administration issued an emergency order early Friday that prohibited all American flights in Tehran-controlled airspace above the Persian Gulf and Gulf of Oman because of "heightened military activities and increased political tensions." The agency said that flight operations in the area were prohibited "until further notice." United Airlines said in a statement that after a security assessment, it had suspended flights between Newark Liberty International Airport in New Jersey and Mumbai, India, that typically fly through Iranian airspace. The German airline Lufthansa said in an emailed statement that its planes would not fly over the Strait of Hormuz and that the diversion area was likely to expand.

A conquering army wants to take a major city but doesn't want troops to get bogged down in door-to-door fighting as they fan out across the urban area. Instead, it sends in a flock of thousands of small drones, with simple instructions: Shoot everyone holding a weapon. A few hours later, the city is safe for the invaders to enter. This sounds like something out of a science fiction movie. But the technology to make it happen is mostly available today -- and militaries worldwide seem interested in developing it. Experts in machine learning and military technology say it would be technologically straightforward to build robots that make decisions about whom to target and kill without a "human in the loop" -- that is, with no person involved at any point between identifying a target and killing them.

DUBAI - The "flying object" that flew over a Japanese tanker before it was rocked by a blast in strategic waters in the Middle East earlier this month could have been a reconnaissance drone, experts have said. The owner of the Kokuka Courageous said the tanker's crew saw a "flying object," just before a blast that caused a fire on board the vessel, sparking a crisis between Washington and Tehran. "The crew members are saying that they were hit by a flying object. They saw it with their own eyes," Yutaka Katada, head of Kokuka Sangyo shipping company, said the day after the mysterious June 13 attack. "We have received a report saying that something seems to have flew in, there was an explosion and it created a hole in the body of the ship," he told reporters in Tokyo.

Autonomous drone racing Drone racing is becoming a major e-sports. Enthusiasts – and now also professionals – transform drones into seriously fast racing platforms. Expert drone racers can reach speeds up to 190 km/h. They fly by looking at a first-person view (FPV) of their drone, which has a camera transmitting images mounted on the front. In recent years, the advance in areas such as artificial intelligence, computer vision, and control has raised the question whether drones would not be able to fly faster than humans.