France, the second nuclear force in NATO

The launch conducted on Saturday represents another test of the future — and variably successful — variant of the ballistic missile MSBS (Mer-Sol-Balistique Stratégique) M51. The M51.3 missile, lacking a warhead, was launched from the Biscarosse missile range in southwest France and fell into the North Atlantic.

The trial of the novel weapon was overseen by French navy ships. They were charged with retrieving the missile debris, among other tasks. The test concluded successfully, according to the official statement.

The M51 is the sixth iteration of the French SLBM (submarine-launched ballistic missile), succeeding the M1, M2, M20, M4, and M45 missiles. The work on this weapon's presently developed variant, the M51.3, escalated following Russia's attack on Ukraine in 2014.

The M51.3 is designed for the current generation of French nuclear submarines, the Le Triomphant class, and future SNLE 3G submarines. The latter is predicted to enter service around 2035 and remain active until 2090.

The M51 is a formidable weapon. The missile weighs 57 tons, spans 39 feet in length, and has a 7.5-foot diameter. Its distinguishing feature is a slightly rounded, blunt end, evocative of designs used in American Trident missiles.

The missile's blunt end implies a more giant volume head, meaning more room for a warhead. The resulting increase in air resistance, significant during initial flight stages, is addressed by a deployable telescopic extension, or "aerospike".

It's a technique first deployed by Russians in the MANPADS 9K38 Igla, where the protruding "needle" (the source of the system's name) minimized the heating of the head, which contains a temperature-sensitive infrared sensor.

In the French ballistic missile's case, the aerospike is a long, extendable arm with a small, round plate at the end. This design reduces aerodynamic resistance, thus enlarging the warhead and expanding the range by a small percentage.

The range for the M51 remains confidential but is thought to be between 6213 and 6835 miles. An essential feature of the M51 is its capability to use an MIRV warhead. This allows up to ten smaller subheads — both warheads with a nuclear charge and decoys — to be placed in one head, designed to confuse the enemy's ballistic missile defense.

The other mainstay of Paris's nuclear arsenal is nuclear warheads delivered by air. Unlike the US, who currently only equip their planes with the dated B61 nuclear bombs, the French have a much more advanced missile solution — the ASMP, currently in the ASMP-A/R variants.

This weapon serves an intriguing purpose. While the M51 missiles are strategic weapons, the ASMP missile has a unique position in the French arsenal. According to France's nuclear weapons use doctrine, they rule out the tactical (i.e., during direct battlefield operations) use of atomic weapons, do not predefine potential target countries, but retain the ability to eradicate the political and economic centers of a potential aggressor.

Moreover, Paris retains the right to be the first to use nuclear weapons to alert a nation posing a threat to France's security. Such a de-escalating warning strike could be executed with the aid of the ASMP missile, the power of whose warhead can be adjusted to a range between 100-300 kt.

The ASMP missiles have been in development since the 80s. The original version was replaced in 2009 by the improved ASMP-A, and the subsequent version, the ASMP-R, is currently being delivered.

This missile weighs 1896 lbs and measures 17.3 feet long. The ASMP-A variant can travel more than 310 miles and reach a high speed, peaking at Mach 3. Presently, France is working on its replacement — the hypersonic ASN4G (Air-Sol Nucléaire de 4ème Génération) missile, which boasts a range exceeding 620 miles and a top speed of Mach 8.

Following the retirement of other ones, the sole French carriers of ASMP-A/R missiles are Rafale aircraft.