British Army

That's a claim they like to make for the sake of provoking flame fests or elevating their own egos. In reality, if you were to audit the knowledge of those who make such claims as to their knowledge of the US military, you're likely to find that they really don't know, and base their claims solely on hearsay. Though one point where the British are due credit is that their soldiers aren't trained solely in one occupation, but rather, two, although how much emphasis is placed on the second, and what level of proficiency they're trained to in their second military occupation can be a bit questionable.

In addition:

It's important to understand a few key differences between the British & US Armed Forces, most notably the matter of size!

The regular British Army is only slightly over 100,000 strong. To this can be added 30-40,000 Territorial Army (equivalent to NG), & a few thousand "Active Reserves" (ie troops recently discharged who may, in an emergency, be recalled). Compare this with the over 500,000 regular US Army, plus nearly as many NG/ Reserves, making a total of a million or so available.

The USMC alone is larger than most other national militaries! It has as many battle tanks as the British Army (about 400), & more combat aircraft than the RAF - the second largest airforce in NATO!

The much greater scale (and budgets!) of the US military enables it to maintain very large/ sophisticated training facilities to which soldiers & marines go, as part of their units/ formations, after basic/ preliminary training. Generally, in the US Armed Forces, "basic training" is just that - basic introduction to the essentials.

The British Armed Forces simply can not afford to operate in this way - economies of scale etc! Lack of "spare capacity" means all soldiers & marines have to be fully fit for operational deployment as soon as they join their units. Therefore, the British approach is to "front load" training & include in the "basic" package a lot of things that the Americans leave until a little later when personnel have joined their units.

Also, because the British Army & Corps of Royal Marines are relatively small, & there's no shortage of eager recruits (despite what some assert!), they can be far more selective about who is accepted in the first place. This is particularly true of the Royal Marines, who actually reject the majority of applicants who attend their 4 day pre training recruit selection course! The huge USMC, with its vastly greater personnel needs, simply could not afford to pre-screen in such a way. Generally, British recruits are, on joining, better prepared physically & psychologically for the transition to military life than are many Americans, & are far more likely to want a long-term military career rather than just a few years service for the benefits which can thereby be accrued.

This largely explains the different approach to initial recruit training: yes, British recruits get shouted at (& punished!), & physically are pushed very hard, but because they're more heavily screened before joining than American equivalents (& more likely to be aiming at a long term career) there is not, generally, the same need for "motivational PT", "smoking" etc.. Significantly, in the days when Britain maintained a huge standing army (600,000+), & compulsory military service of 2 years was required of all adult males (with few exceptions - thus ensuring many recruits were not very motivated to serve), the approach to recruit training was very like the US model; shaved heads, lots of eyeball to eyeball stuff, collective shouting/ chanting etc..

So, it's not really about "longer" or "tougher" training; rather it's about how & when exactly things get done. Both militaries have their tried & tested training systems, geared to their particular needs & circumstances. Each works very well in its context, producing some of the best trained combat marines & soldiers in the world. It's far better to compare marines & soldiers of the different forces after about 2 years in service, & generally the overall quality is comparable.

A good illustration of this would be to consider infantry training in respective airborne formations. The British Parachute Regiment is tough to get into - very tough! Recruits endure 28 weeks of rigorous training which includes the notorious & brutally hard "Pre Parachute Selection Course" (P Company), plus a very harsh & realistic 10 day "battle camp" (minimal sleep, limited food, endless live firing scenarios, long distance "advances to contact" carrying very heavy loads etc), and ends with the basic Parachute Course. Frequently only 30% of recruits survive to actually take the parachute course & join one of the Para Regt battalions.

In contrast, joining the infantry of the 82nd Airborne is relatively easy: 9 weeks Basic Combat Training, + 5-6 weeks Infantry AIT (usually one station training at Ft Benning), followed by basic Airborne School of 3 weeks. Yes, this includes a lot of PT, but nothing comparable to the brutal speed marches with 60lb loads, log & stretcher races, "milling" etc faced by P Company recruits. However, once with the infantry battalions of the 82nd, the new soldier had better perform well in unit training (which will include plenty of long ruck marches & other physical & military skills tests), & if he doesn't will find himself transferred out to a less demanding unit. Those who survive in the Airborne/ Parachute Infantry battalions for a year or so will have been just as rigorously trained/ tested as the Brits.

So, the American approach is to "select out" already trained soldiers who prove incapable of maintaining the required standards for Airborne Infantry. This is sustainable/ cost effective in a very large army, whereas the much smaller British Army can not afford the expensive parachute training of soldiers who may then prove unsuited to the airborne role.

A similar pattern is evident in the two Marine Corps. Royal Marine recruits undergo 8 months of training at the Commando Training Centre, including the Commando Course: extreme endurance training, close quarter battle & unarmed combat, plus a lot of tactical work - basic reconnaissance, raiding, & demolitions, amphibious ops, heliborne ops, cliff assault etc..

United States Marine recruits who branch Infantry undergo 3 months of "basic" (Boot Camp), plus 2 months infantry specific training at the Infantry School. Then they typically join an MEU, & during the MEU training cycle will be introduced to a lot of the stuff that RMs will have done during their "basic training".