WASHINGTON () Ukraine’s recent crippling attack on Russia’s bomber fleet raises new concerns that the U.S. is unprepared for a drone attack on American soil.

Lawmakers from both parties who have spoken with agree that American airspace is vulnerable, and the highly-strategized Ukrainian drone shows just how much damage a relatively inexpensive drone can do to a multimillion-dollar aircraft, as was the case in Russia.

The targets were Russian warplanes, including strategic bombers and command-and-control aircraft, worth hundreds of millions of dollars. The weapons were Ukrainian drones, each costing under $1,000 and launched from wooden containers carried on trucks.

“Operation Spiderweb,” which Ukraine said destroyed or damaged over 40 aircraft parked near air bases across Russia on Sunday, wasn’t just a blow to the Kremlin’s prestige. It was also a wake-up call for the West to bolster its air defense systems against such hybrid tactics. How deeply the attack will impact Russian military operations is unclear. Although officials in Kyiv estimated it caused $7 billion in damage.

Army Secretary Daniel Driscoll and Federal Aviation Administration Chief Chris Rocheleau were recently grilled during Capitol Hill testimony on the safety of American airspace.

spoke exclusively with U.S. Sen. Andy Kim, D-N.J., who says there are problems with the airspace when it comes to detecting drones or incursions. He says, at this point, the U.S. still cannot do that in an efficient way to prevent what could be a serious threat.

Kim pointed to recent mysterious drone sightings over the Garden State, sightings that Transportation Secretary Sean Duffy still cannot explain.

“Regardless of what was flying up in the skies in New Jersey, the fact that our military bases didn’t know what was going on, nor did they have a clarity of how they would have responded if it was something dangerous or nefarious, shows that we’re just not at the level of readiness to be able to take this on,” said Kim. “And this isn’t just about our military bases. It’s about critical infrastructure, water treatment plants, power plants.”

Back in January, newly sworn-in President Donald Trump said all of what were seen over New Jersey were FAA-authorized aircraft, a break from what Duffy told .

Senators who spoke with said that in the not-so-distant past, the FAA and the Department of Defense were not necessarily communicating with each other. Sources tell the two agencies are now sharing more information when it comes to drone sightings.