I always figured the number of Tomahawk cruise missiles in the Navy inventory was a classified number. Turns out, the Navy has been publishing the number since at least 1997.

The Navy also, between 1997-2000, published the number of TLAM/N nuclear warheads.

Amazing the things you learn from the defense budget.

1.

Let’s start with the Tomahawk inventory.  I remembered the debate over Operation Allied Force, when some members of Congress were concerned that Operation Allied Force might deplete the inventory. Ron O’Rourke wrote a report for CRS that attempted to estimate the inventory based on public sources.

Turns out, the Navy has been publishing the inventory (TLAM/C-D/TacTom) all along in the O&M book, which is conveniently online dating back to FY1998:

FY97 FY98 FY99 FY00 FY01 FY02 FY03 FY04 FY05 FY06 FY07 FY08 FY09 FY10 FY11 FY12 FY13
2506 2667 2158 2139 2192 2253 1499 1624 1902 2250 2695 3038 3035 3845 3809 3755 3699

Source: DEPARTMENT OF THE NAVY, “OPERATION AND MAINTENANCE, NAVY,” FISCAL YEAR (FY) 1998-2013 BUDGET ESTIMATES, JUSTIFICATION OF ESTIMATES (Published Annually, 1997-2012). Here is a link to the FY2013 edition. Notes: The O&M book lists numbers for the preceding, current and next fiscal year. I generally used the preceding year number. So, for example I took the FY1997 number from the FY1999 budget request, which would have been released in February 1998. Obviously that doesn’t hold for FY2012 and FY2013.

The impact of Operation Desert Fox and Operation Allied Force on cruise missile inventories was very modest, despite concerns the Navy might run out of cruise missiles. (Admittedly, newer blocks might have been depleted first.)  Operation Enduring Freedom and Operation Iraqi Freedom, on the other hand, resulted in a larger depletion of the cruise missile stockpile, although the Navy still had a significant number of TLAMs in reserve and quickly replenished the inventory.  (I think of a “significant reserve” as more missiles in the inventory than were expended in the operation.) GAO, by the way, revealed the level of depletion in December 2003:

During Operation Iraqi Freedom, 789 Tomahawks were expended with a remaining inventory of 1,474

The numbers are probably slightly different given the date that the inventory was calcuated, although they are in general agreement.

I guess we can lay the issue of inventory depletion to rest, as well as concerns about declaring the size of the inventory.

2.

In the course of looking at cruise missile warheads, I noticed a strange entry: nuclear weapons warheads.  I rubbed my eyes.  Nuclear.  Weapons.  Warheads.  Holy crap! The Navy, between 1997-2000, listed the number of TLAM/N warheads:

FY96 FY97 FY98 FY99 FY00 FY01
337 338 336 334 334 334

Note: I used the same procedure as above, with the result that FY2000 and FY2001 were projections made in February 2000.

A few observations. First, HOLY CRAP. Second, in 1998, Stan Norris and friends estimated the size of the W80 stockpile for the TLAM/N at 320. I’d say that was a pretty damned good estimate.

Third, in the FY2001 President’s Budget Submission (and only in the FY2001 PBS) the Navy listed 157 for the category “Nuclear Missile (TLAM/N) Supported.” In subsequent years, that category disappeared, while the general category for “missile inventory” suddenly included an explicit definition of its contents, including “TLAM”, as well as TLAM/C-D and TacTom. That change in wording leads me to believe that in the FY2001 submission, the Navy was breaking out (and revealing) 157 TLAM/N airframes.

Two warheads per airframe would be consistent with the general US approach to hedging, albeit in an instance where the US has only one warhead design that might suffer aging-related defects across the entire class. It also is possible that the Navy had 300 plus TLAM/N airframes and had simply defunded the portion deemed excess. The entry only exists for the FY2001 budget submission, so I can’t really tell.

3.

The upshot of this rather surprising revelation is that the United States should surely consider, in any agreement with the Russian Federation regarding SLCM data exchanges, the reciprocal exchange of data about the total inventory of cruise missiles and the number of nuclear warheads assigned to TLAM/N, including historical data.  After all, the TLAM/N will no longer be in the active stockpile and a significant portion of the historical inventory is a matter of public record.

I can’t help but add that this surprising revelation demonstrates the transparency that arises from defense budgeting in a participatory democracy, as well as how analysts can use that information to inform policy debates — even if I was a bit late to the party.