Why the US Navy Needs Non-Nuclear Submarines

The Defense News recently reported that the US Navy’s submarine commander’s course now requires nuclear-powered subs (SSN) and nuclear-powered subs armed with nuclear missiles (SSBNs) to conduct one-on-one mock combat with each other. This is a major breakthrough for USN submarine training, one that I have been calling for for many years. Indeed, Vice Admiral William Houston, the Commander of the Naval Submarine Force said “what we are finding is tactics on SSNs and SSBNs operating together that we either had forgotten about or we did not know. It is tremendously powerful.” (1)

Indeed, it is, but it only involves USN nuclear submarines, which Admiral Houston says are the “best in the world” (2), which is debatable, but that is not the purpose of this article. He didn’t say US submarine captains are the best in the world, which is good, because as I pointed out in my 2007 book, Lessons Not Learned: The U.S. Navy’s Status Quo Culture, that is simply not true due to the focus on engineering over war fighting, the careerism and the risk averse culture of the USN (3).

This conclusion was recently confirmed by a friend named Commander Kerry Gentry who commanded an SSBN and told me that even today only about 20% of USN submarine captains stand a chance of defeating a first class enemy submarine, especially those commanded by captains who were trained by the British or Dutch, and many countries can make that claim, even though the Royal Navy no longer operates diesel boats, which I think was a mistake. He’s retired now, but he keeps track of these things and it would be wise for the USN to actually listen to constructive criticism from former senior officers who have the experience to know what they are talking about. Gentry was never a “yes man” so he retired as an O-5. He was a highly effective SSBN skipper, and might have made admiral if the USN were more open-minded to thoughtful advice from concerned officers that know that this organization is too expensive, and does not live up to Tom Clancy’s “we’re the best” propaganda. He even told me that the silent service is more like a cult still based on the domineering personality and pro-nuclear brainwashing of Admiral Rickover, who passed away decades ago, but remains a strong influence nevertheless. He and his disciples believed that real navies use only nuclear submarines, but it is time to get past that.

What I would like to point out is that this would be the ideal time to reconsider having only nuclear submarines in the USN, and as the respected military reformer and author Chuck Spinney suggested in an article I wrote for the Project on Government Oversight, that it build its own Air-Independent Propulsion (AIP) submarines to serve as aggressors for this kind of training. (4)

I am not saying the USN should abandon nuclear submarines, but rather consider building a small number of AIP boats to make sure that future submarine captains have had experience dealing with the difficulties of doing combat with highly capable AIP submarines that are now operated by navies all over the world. It has already borrowed such a submarine from the Royal Swedish Navy, and should investigate doing so again during the interim until the USN has its own dedicated AIP Aggressor Squadron. This will take many years, but there is no substitute for a superpower to having all the necessary platforms to fight and win wars, without help from anyone else.

As I have said before, it is time for the USN to stop acting like an ostrich and take action to effectively defend America from potential adversaries like China. According to The National Interest writer Kyle Mizokami, “Chinese submarine technology has grown by leaps and bounds over the last three decades, moving quickly from aging Romeo class diesel-electric submarines to more modern designs. One of China’s latest submarine classes is the Type 039A or Yuan class submarine. The submarine is roughly similar to the Soviet/Russian Kilo class, with a bullet-shaped hull and large sail, but at 3,600 tons the Yuans are twenty percent larger. The submarines have a top speed of twenty knots submerged and are the first Chinese submarines to use AIP, reportedly the Sterling system. The class is equipped with six 533-millimeter standard diameter torpedo tubes capable of launching torpedoes, Klub anti-ship missiles, C-802 anti-ship missiles or sea mines.” (5)

The author doesn’t state if or why larger subs are better, but he noted that the Sterling system is not the most advanced AIP system available and other countries have better AIP boats, but if the Chinese have AIP boats, isn’t it reasonable for the USN to learn how to deal with them by building some of their own?

Winslow T. Wheeler, former Director of the Center for Defense Information,  has pointed out recently that conventional submarines are less expensive, quieter, and capable of defeating submarines from the USN, so it is high time to get over the “nuclear only” dogma that had undermined US combat capabilities for decades.(6)

Let’s hope that this newly revised training will be the beginning of a renaissance in USN submarine training and tactics. It is long overdue, and a pleasant surprise to me, a writer who has focused on the USN since graduate school. The purchase of AIP submarines that typically cost between $200 million and $600 million, as compared to $2.6 billion dollars for an American SSN (7) would give us excellent submarines for less money, and would be proof that the Navy takes national security seriously and is willing to face reality and learn from other countries who have operated these deadly conventional submarines for decades.


1)  Megan Eckstein, “Better weapons, complex training bolster US submarine force”, Defense News, November 4, 2020, www.defensenews.com/naval/2022/11/03/better-weapons-complex-training-bolster-us-submarine-force/

2) Ibid.

3)   Roger Thompson, Lessons Not Learned: The U.S. Navy’s Status Quo Culture (Annapolis: Naval Institute Press, 2007), pp. 10-40.

4) Roger Thompson “Take Her Deep: Reforming the U.S. Silent Service” Project on Government Oversight, October 31, 2013.

5) Kyle Mizokami, “AIP Submarines: The Warship Of The Future?The National Interest, March 18, 2021.

6)   Winslow T. Wheeler, “The AUKUS Nuclear Attack Submarine: Good Luck with That, Australia” Real Clear Defense, Oct 9, 2021.

7)  Sebastien Roblin, “Nuclear or Not? Why the U.S. Navy Doesn’t Want AIP SubmarinesThe National Interest, May 28, 2021.

Roger Thompson is a research fellow at Dalhousie University’s Centre for the Study of Security and Development, the author of Lessons Not Learned: The US Navy’s Status Quo Culture, a former researcher at Canada’s National Defence Headquarters and Korea’s first Star Trek professor.