Ukraine, in its latest sneak attack, has landed powerful blows on a sacrosanct Russian institution: the summer vacation. In a one-two punch, Ukraine sent drones near St. Petersburg’s international airport, grounding thousands of would-be vacationers, many already dressed in resort wear. Then, cyber hackers brought down Russia’s largest airline, Aeroflot.

It may take six months for Russia’s national flag airline to fully restore service. As the departure board at Aeroflot’s Moscow hub, Sheremetyevo, turned red with cancellations, two pro-Ukraine hacker groups, Silent Crow and Belarusian Cyberpartisans, said today they had worked inside the airline’s computer network for the last year. 

They said they destroyed 7,000 servers, gained control of senior managers’ personal computers, and stole 20 terabytes of data. They promised to release emails of the state-owned company and the personal data on all Russians who have flown recently with Aeroflot. Given that Aeroflot carried 55 million passengers last year, this could mean the entire middle class of Russia, a nation of 144 million people.

 “This is a serious disaster. Okay, flight delays — you can survive that,” a former Aeroflot pilot and aviation analyst, Andrei Litvinov, told Reuters. “If all the correspondence, all the corporate data is exposed — this can have very long-term consequences. First the drones, and now they are blowing up this situation from the inside.”

One angry Aeroflot ticket holder, Yulia Pakhota, posted on the VK social media site: “The call centre is unavailable. The website is unavailable. The app is unavailable.”

Earlier this month, Ukrainian drones forced airlines to cancel 485 flights and delay 1,900 others at Moscow and St. Petersburg. Yesterday’s drones over St. Petersburg came after the Russian navy had already canceled its traditional Navy Day flotilla of warships and military vessels on the Neva River. 

After a series of mystery bombings of Russian cargo ships this year, the live review of vessels was canceled due to “security concerns.” Yesterday, Mr. Putin settled for watching naval reviews on video screens in the Russian navy’s 19th century Admiralty building. The plane carrying the Kremlin press pool was delayed for two hours due to Ukrainian drones.

In a potentially more serious threat to Russia’s leader, 

President Trump announced today that he is advancing to August 10 his deadline to impose tariffs on countries buying Russian oil. “There’s no reason to wait. If you know what the answer is going to be, why wait?” President Trump said to reporters today in Scotland. “And it would be sanctions and maybe tariffs, secondary tariffs.” 

Earlier this month, Mr. Trump had set a September 2 deadline for Mr. Putin to reach a cease-fire with Ukraine. Initially, oil traders yawned at the threat. This time they jumped. Within minutes of Mr. Trump’s statement, prices were up by 3 percent.

“The real story in recent days has been the growing evidence that Putin is making a serious miscalculation regarding Trump’s policy and the staying power of the West,” a former American ambassador to Ukraine, John E. Herbst, wrote Friday for an Atlantic Council article under the headline: “Putin may be miscalculating Trump’s resolve on Ukraine.”

Last week, India’s largest company, Reliance Industries, announced that it is diversifying its oil purchases away from Russia. Under the Trump plan announced July 14, America would impose 100 percent tariffs on all companies and countries buying Russian oil.

From Moscow, a former Russian president, Dmitry Medvedev, posted today on X: “Trump is playing the ultimatum game with Russia. … Every ultimatum is a threat — a step toward war. Not with Ukraine, but with his own country.”

For superstitious Russians, this attack on sales of their no. 1 export — and on their August vacations — revives talk of the dreaded “August Curse.”

Due to a mix of summer torpor and official inattention, bad things happen in Russia in August. The list is long: the outbreak of World War 1 (“The Guns of August”); the start of the Battle of Stalingrad in 1942; the failed “August Coup” by communist hardliners in 1991; Russia’s defeat in the first Chechen war; the 1998 financial crisis; and the 2008 Russia-Georgia war. Over the last 25 years Russia has endured in August: apartment bombings, aircraft bombings, train bombings, the collapse of a Siberian hydropower plant, and a submarine sinking in the Arctic.