Ukraine’s shock drone strike on Russia’s strategic bomber fleet this week has generals and analysts taking a new look at threats to high-value United States aircraft at bases in the homeland and abroad – and the situation is worrisome.

Officials say Ukraine was under an ongoing Russian ballistic missile and drone attack early Friday that wounded at least three people.

Four people were killed and more than 50 injured in Ukraine after Russia pummeled targets across the country with drones and missiles for a second straight night.