WILLIAM BRANGHAM: Welcome to the "News Hour."

The Trump administration today announced an immediate pause on the leases for five large-scale offshore wind farms off the East Coast, citing concerns about national security.

The Interior Department provided few details, but said the Pentagon believed the turbines could obscure and confuse radar signals.

This is just the latest move by the White House taking aim at wind power.

At least one of the projects halted today was already partially operating.

Our science correspondent, Miles O'Brien, has been reporting on these projects and joins us now with the details.

Miles, what is the reaction you have been hearing from the states, from the companies about this move today?

MILES O'BRIEN: William, it's a little bit of a Groundhog Day effect, one more time, sort of the same arguments, and there's a sense of resignation and, frankly, quite a bit of sadness.

There's a huge amount of money that's being lost, even as we speak.

And this idea of putting wind offshore to feed the cities, the population centers along the East Coast first took root about 25 years ago, really began going in earnest about 10 years ago, went through layer after layer of approval and permitting process, which included the Federal Aviation Administration and the Department of Defense to determine if, in fact, these turbines might pose a threat to radar and the ability for radar to track aircraft.

Ultimately, it passed all of those tests, the permits were granted, and now billions have been spent to put these turbines in the water and, in many cases, already connect them to the grid.

And so the idea that, after all that, it might come to naught leads to a lot of resignation and sadness.

And many of the people we spoke with almost felt like they had received yet another body blow on a long-term effort that they thought they had come close to realizing.

WILLIAM BRANGHAM: As I mentioned, the Interior Department said that the Pentagon had discovered new issues with regards to radar that you were just describing.

This is how Interior Secretary Doug Burgum put it on FOX News earlier today.

DOUG BURGUM, U.S.

Interior Secretary: The Department of War has come back conclusively that the issues related to these large offshore wind programs have -- create radar interference that creates a genuine risk for the U.S., particularly related to the -- where they are in proximity to our East Coast population centers.

WILLIAM BRANGHAM: Miles, I know you have talked with a lot of people who have looked at this issue.

What do they say about these concerns?

Are they legitimate?

MILES O'BRIEN: Well, first, radar do see these turbines.

They are as tall as the Eiffel Tower, on or about 1,000 feet.

So, of course, they're going to see them.

There's no question they create an interference pattern.

But a couple of things here.

First of all, having flown through these turbines myself in a small aircraft, the FAA is well aware of the obstacles, where they are.

It's not like they're moving anywhere.

And they're able to identify these problems for traffic that might run afoul of it.

As for a threat coming in, there are all kinds of ways to mitigate against that problem by either improving the radar coverage, adding additional radar that can sort of peek through the turbines, reducing the radar reflectivity of the turbine blades, any number of ways.

And I should point out, while the turbines do make more radar noise, if you will, while they're spinning, if the projects are shut down, as the Trump administration wants to do, those turbines are still sitting in the water.

Those obstacles are still there.

So it's hard to see how this remedies that particular problem if you would accept for a moment that it is, given the fact that the Pentagon has looked at this dozens of times over the years.

WILLIAM BRANGHAM: Taken together, all of these projects were going to power I believe it's 2.5 million homes and businesses along the East Coast.

I mean, these are massive clean energy projects.

What happens now?

Is there an alternative to supplying that power?

What's next?

MILES O'BRIEN: In the Northeast, they have doubled down on offshore wind.

We talked to the grid operator in New England, ISO New England, and they have approximately 37 gigawatts of power in the interconnection queue, as they call it; 45 percent of that is offshore wind, 45 percent of that battery, and 10 percent of that is solar.

So there really aren't any viable options right now on the near-term horizon for the Northeast.

If you wanted to think about alternatives, building fossil fuel plants, it takes five, six, seven years just to get a gas turbine delivered.

Certainly, nuclear is an even longer time frame.

And the country is facing an unprecedented, near-unprecedented increase in demand for energy driven by the electrification of the economy and the rise of these A.I.

data centers.

And if you really want to look at a national security issue, an unstable grid that is unable to support that growth in the need of energy, that is a true security threat.

WILLIAM BRANGHAM: Miles, as we have reported repeatedly and we have talked about quite a bit, this is just the latest in the Trump administration's efforts to undo renewable energy and to double down on fossil fuels.

What are the long-term ramifications of that?

MILES O'BRIEN: It's an inopportune moment.

William, 70 years of flat demand for electricity in the U.S., now there's a huge uptick thanks to the electrification of the economy and A.I.

data centers.

Every expert I have spoken to says every possible option needs to be on the table in order to meet this demand.

WILLIAM BRANGHAM: Miles O'Brien, always great to talk to you.

Thank you so much.

MILES O'BRIEN: You're welcome.