The US Army is telling its soldiers 'you have to look up' as it watches Abrams tanks face new threats in Ukraine

• Drones have proven a menace to armored vehicles in Ukraine, including US-provided tanks.
• The US Army is closely watching the drone war and teaching lessons to new soldiers in training.
• A colonel at the Army's Armor School told Business Insider that he's telling soldiers they have to "look up."

US-made armored vehicles in service with the Ukrainian military are up against an unfamiliar threat on the battlefield, one that they haven't faced in previous wars.

Russia and Ukraine employ small drones strapped with explosives as a way to deliver cheap and effective precision strikes on enemy armor, often damaging or destroying them.