We take a look.
In the early 2000s, the U.S. Army pondered replacing stocks of Beretta M9 service handguns with a new, more powerful handgun. The Pentagon cancelled the program but one of the contenders, Heckler and Koch, eventually released its entry into the civilian market. Designed with the assistance of U.S. special operations veterans, the HK45 is one of the most advanced .45 ACP pistols available today.
In 2005, the U.S. Army merged two parallel pistol programs, the Army Future Handgun and Special Operations Forces Combat Handgun program, into a single effort to field a new pistol. Soldiers had long grumbled about the then-current duty handgun, the 1980s-era M9. This was born out by a 2006 CNA field report on U.S. Army small arms (PDF), which reported soldiers in Iraq and Afghanistan lacked confidence in and satisfaction with the Beretta-made pistol.
The new effort, the Joint Combat Pistol Program (JCPP), reversed the decision to move from .45 ACP to 9mm Luger, calling for a .45 pistol with a M1913 STD Picatinny rail, day and night sights and a threaded barrel for attaching a suppressor. The Army potentially involved a purchase of 600,000 pistols for all the armed services. Like several high-profile Army programs in the mid-2000s the JCPP was also cancelled, the victim of belt-tightening. A new pistol wouldn’t enter service until 2018.