To attack deep within enemy territory and help overcome high-tech challenges posed by emerging adversary air defenses.
A cruise missile armed with nuclear weapons could, among many things, potentially hold targets at risk which might be inaccessible to even stealth bombers, given the growing pace at which modern air defenses are able to detect a wider range of aircraft - to include the possibility of detecting some stealth bombers.
As a result, senior Air Force leaders continue to argue that engineering a new, modern Long-Range Standoff weapons with nuclear capability may be one of a very few assets, weapons or platforms able to penetrate emerging high-tech air defenses. Such an ability is, as a result, deemed crucial to nuclear deterrence and the commensurate need to prevent major-power warfare.
Therefore, in the event of major nuclear attack on the US, a stand-off air-launched nuclear cruise missile may be among the few weapons able to retaliate and, as a result, function as an essential deterrent against a first-strike nuclear attack.
“Deterrence works if our adversaries know that we can hold at risk things they value. This weapon will enhance our ability to do so," Air Force Secretary Heather Wilson said in a written service statement.
With this goal in mind, the Air Force recently awarded two $900 million LRSO deals to both Raytheon and Lockheed Martin as a key step toward selecting one vendor for the next phase of the weapon's development. Due to fast growing emerging threats, the Air Force now envisions an operational LRSO by the end of the 2020s - as opposed to prior thoughts they it may not be ready until the 2030s.
“LRSO will provide the next generation strategic deterrent missile for the air-launched portion of the nuclear triad,” David Helsel, LRSO program director at Lockheed Martin Missiles and Fire Control, said in a written statement.
The LRSO will be developed to replace the aging AGM-86B Air Launched Cruise Missile or ALCM, currently able to fire from a B-52. The AGM-86B has far exceeded its intended life span, having emerged in the early 1980s with a 10-year design life, Air Force statements said.
Unlike the ALCM which fires from the B-52, the LRSO will be configured to fire from B-2 and B-21 bombers as well, service officials said; both the ALCM and LRSO are designed to fire both conventional and nuclear weapons.
While Air Force officials say that the current ALCM remains safe, secure and effective, it is facing sustainment and operational challenges against evolving threats, service officials also acknowledge.
The rapid evolution of better networked, longer-range, digital air-defenses using much faster computer processing power will continue to make even stealth attack platforms more vulnerable; current and emerging air defenses, such as Russian-built S-300s and S-400s are able to be cued by lower-frequency “surveillance radar” -- which can simply detect that an enemy aircraft is in the vicinity -- and higher-frequency “engagement radar” capability. This technology enables air defenses to detect targets at much farther ranges on a much larger number of frequencies including UHF, L-band and X-band.
Russian officials and press reports have repeatedly claimed its air-defenses can detect and target many stealth aircraft, however some US observers believe Russia often exaggerates its military capabilities. Nonetheless, many US developers of weapons and stealth platforms take Russian-built air defenses very seriously. Many maintain the existence of these systems has greatly impact US weapons development strategy.
Accordingly, some analysts have made the point that there may be some potential targets which, due to the aforementioned superbly high-tech air defenses, platforms such as a B-2 stealth bomber or services now-in-development next-generation bomber, the B-21, might be challenged to attack without detection.