I don't think you understand the implications of it and you're being bizarrely and entirely inapporporiately political about something that is national security related.
(1) A more accurate bomb is more destructive than a larger, less accurate bomb. One of the reasons the US is able to retire the unguided B83 1.2Mt City Buster is because a guided B61-Mod 12 at 50kt has broadly superior destructive power. As the paper I quoted said, doubling a bomb's accuracy increases it's destructive power eight fold. The B61's accuracy is increasing much more than that due to the tail fin integration, which allows it to be smaller.
(2) Every single weapon in existence has an expiration dates, and it's been decades since the US produced some of these weapons. In coming decades some nuclear weapons will have to be replaced regardless, because the conventional explosives which start the reaction will be unsafe for use. And beyond that by 2091, most of the nuclear cores themselves will have decayed.
This means the US will need to remanufacture weapons. In given the choice between building more B83s in a seperate multi-billion dollar program, or consolidating five types of bombs into two types and enjoying the cost savings, the answer seems obvious.
(3) A smaller nuclear weapon makes it more "usable". This has been one reason anti-nuclear campaigners have been against the B61 and other low-yield nuclear weapons. They are deeply concerned - with good reason - that the smaller a nuclear weapon gets, the more likely the US or someone will feel comfortable using it. This is particularly true of the B61 Mod 12, whose lowest yield setting, 0.3 kilotons, or 300 tons, would be "just" 27 times as powerful as MOAB (11 tons of TNT)
As you can see a 0.3kt explosion is small
https://nuclearsecrecy.com/nukemap/?...hob_ft=0&zm=16
But this was entirely the point. To destroy air bases outside of cities, but not cities. To destroy hardened sites, but limit radiation fallout.
The only reason nuclear warheads were historically enormous was because the technolgy for accuracy didn't exist. When a warhead could miss by a kilometer and a half, it needed to be enormous so that even a "miss" still destroyed or seriously damaged its target.
Further if you read the article I linked, you'll see the rationale behind "superfuses" and it applies to B61-12. The most destructive area of a nuclear explosion (or any explosion really) that is an air-blast is directly below it.
A small bomb that detonates directly above its target is much more destructive than a large bomb that detonates tens or hundreds of meters away.
(4) The US nuclear arsenal has been consolidating for 20 years for good reason - the Cold War era arsenal was aging, and too complex to sustain indefinetly, especially when aimed at fewer Russian targets than ever. Let me explain what I mean.
30 years ago, the US had the following weapons in it's nuclear arsenal
4 different types of ICBM (Titan II, Minuteman II, Minuteman III, Peacekeeper)
4 types of bombs with many sub-families (B43, B54, B61, B83)
many, many types of Warheads (W88, W87, W76, W78, W84, W85, W80, W68, W69, W79, and more)
3 types of SLBM (Poseidon, Trident I, Trident II)
3 types of Nuclear Cruise Missile (AGM-86 ALCM, AGM-129 ACM, BGM-109G)
A huge number of tactical nuclear weapons (such as nuclear land mines and depth charges).
Some of these had some commonality. Many did not, even if they had similar names (Trident I and Trident II were hugely different for example). But every single one required an independent standing industrial base to support them. And that's tremendously expensive. Not even to BUILD new weapons, but just to keep existing ones working.
Currently the US nuclear arsenal consists of:
1 type of ICBM (the Minuteman III)
2 Types of bombs (B61 with 5 subvariants, B83)
1 type of SLBM (Trident II)
5 types of warheads (W88 , W87, W76, W78)
1 type of Nuclear Cruise Missile (AGM-86)
No more nuclear landmines, depth charges or shells. B61s in lower yields fill the tactical role.
Cost savings and strategy drove all of this.
For example, a decade and a half ago the US had the Older Minuteman III and the much newer and more advanced Peackeeper MX. It decided to retire the Peacekeeper MX and put it's warheads on the Minuteman III. Why? Because under the SORT treaty, the US had to retire warheads and missiles to hit the cap. Peacekeeper could carry 8-12 warheads. Minuteman III could carry 3. The US decided to keep the larger share of it's deterrent on the (more useful) submarine launched ballistic missiles, which necessitated having fewer warheads on land based ICBMs. To do this, the US decided to put one warhead on each of it's ICBMs (a larger number of ICBMs being a bigger target for Russia), which made the huge size (and expensive) of the peacekeeper uncessary.
Another example is with the Nuclear Cruise Missile. The stealthy AGM-129 ACM was far more advanced than it's direct predecessor, the AGM-86 ALCM. But it was also significantly more expensive to own.
The best example though is with the Trident II though. The Trident II (1985->) was a quantum leap ahead of the Trident I (1979->2005)and the Poesidon (1971->1992), and for decades the US operated an enormous ballistic missile submarine fleet (41 for Freedom). This was tremendously expensive because it caused a huge diversity of weapon systems (and thus costs). Starting in 1980, the Ohio-class submarine began to be introduced and it was Armed with the Trident I. The Navy rapidly moved to shif tot an all-Ohio class fleet, and rapidly retired its direct predecessor, the Benjamin Franklin class (and the rest of 41 for Freedom classes) which were armed with the Polaris missile or the Poseidon. Some Benjamin Franklin classes were armed with the Trident I, but never were modified to carry the larger Trident II. As soon as the navy could shift to an all Ohio + All Trident II fleet, it did, even though it was replacing 41 nuclear submarines with 14.
In fact the Navy is doing that again: it plans to replace all 14 Ohio-class SSBNs with 12 Columbia-class SSBNs over the next few decades. However the Columbia-class has a life-of-the-ship nuclear core and will never need to be refueled, which means they'll get more-deployments per ship. As a result they don't need to buy the two extra because unlike the Ohio class, two ships won't be out of service for 4 years being refueled. This makes the cost of sustaining the fleet cheaper.