The USS John S. McCain and an oil tanker collided off of Singapore early Monday morning. The accident left 10 U.S. sailors missing and injured others.

This is the second major collision this summer. The USS Fitzgerald, another ship of the Pacific-based 7th Fleet, collided with a container ship in waters off Japan in June. The two Navy ships, which have ballistic missile defense capabilities, are now out of commission. The U.S. Navy’s top admiral John Richardson has ordered an “operational pause” for Navy fleets around the world as well as a separate investigation into the 7th Fleet’s performance and readiness.

The 7th Fleet is the U.S. defense presence in the Indo-Asia Pacific region. So we wondered, with the escalation of words between President Trump and North Korean leader Kim Jong Un reaching new heights in recent weeks, what does the loss of the the USS John S. McCain mean for U.S. defenses?

The PBS NewsHour spoke with Bryan McGrath, a former Navy commander who served from 1987 to 2008. McGrath is now a consultant, the founding managing director of The FerryBridge Group LLC, which specializes in naval and national security issues. The following conversation has been edited for clarity and length.

How important is USS John S. McCain?

We don’t have a limitless supply of ships. We have close to two dozen ships in the Northwestern Pacific at any one time. Only a certain number of them are configured to contribute to the nation’s ballistic missile defense system. The USS John S. McCain is one of them and so was the Fitzgerald, the ship that had a collision two months ago. So this is two out of probably close to a dozen and a half of these ships that we rely upon to help provide targeting data on the ballistic missile shots of interest. That would include those that could potentially come from North Korea.

They provide defense from North Korea?

If North Korea was to shoot an ICBM [intercontinental ballistic missile] in the direction of the United States, they would get an early track on it, and they could help provide targeting data to other elements of the ballistic missile defense system.

So can this ship also shoot down or intercept North Korean missiles?

I am certain the ship cannot intercept a North Korean missile that would be shot at the United States of America. I believe it has some capability against some of the shorter range missiles that it might seek to shoot against its neighbors.

What types of missiles does the ship carry?

The ship carries a variety of missiles, missiles that carry computers so that you can shoot a missile or torpedo into the water and then go get a submarine. It has missiles that shoot down other missiles, it has missiles that shoot down airplanes, and it has missiles that can attack targets on land. Tomahawk missiles, the standard missile family and the vertical launch ASROC [Anti-Submarine Rocket] are the names of those capabilities.

Can you put this accident in context? What does this mean for our defense system in that region?

There are so many layers to this. There’s the nagging question about whether there is something wrong with the U.S. Navy at a systemic level, that oh my goodness, we’ve had these series of accidents, some of them very serious, some of them with loss of life in the last year. Is there something wrong with the Navy and with respect to our country’s defensive posture in that part of the world? The Navy and the Marine Corps are huge components of our defense presence. They are the face of the American dense presence in the western Pacific.

There’s also the direct impact that this ship will not be available for tasking. So there are tasks that will either go unmet or other ships will have to take on additional tasking.

Then there’s the sort of atmospheric question of doubt, of confidence. And I think that’s something the Navy, with regard to the investigation, has to take on. It has to be able to show the American people and our allies around the world that if there are systemic problems, they understand what they are, and they understand how to overcome them. And if there aren’t systemic problems, they must be are able to adequately explain why so many closely spaced horrible accidents have occurred. I don’t think the Navy will reach that latter conclusion. I think they will conclude there are systemic issues that they have to tackle, and I think they will take them on head first.

Is there anything else that you think NewsHour readers should know about?

I think that they should know that there really is no organization that I know of that values accountability and responsibility more than the U.S. Navy. In fact, the Navy is often criticized for … the punishments that are handed out. We have no idea what happened here, we have no idea if this commanding officer would be punished or not, but we do know that the Navy will go after this story relentlessly, they will figure out what happened here, they will figure out what happened in the Fitzgerald two months ago and the other incidences in the Pacific Theater in the past year. And if they are able to draw systemic conclusions, they will release those conclusions, they will let the American public know what is wrong, if anything. And I think your readers should be confident that they’re going to get the truth out of the Navy on this.