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.

Drones are “ubiquitous, because they are quite useful, and they're demonstrating that every day in Ukraine,” one analyst told NBC News.

At least three were killed and 49 injured in a missile-and-drone attack that focused on Kyiv, days after a daring assault on Moscow’s bomber fleet.