M-1 Abrams tanks replaced M60's. M60's replaced M-48's. There were various other Mediums and Heavies between the M-48 and the M4 Sherman. It seems you need to do a little more studying, no, a lot more.
I will reprint this reply from Iraq (not from me) with only one comment. Rumsfeld successfully killed a SP howitzer program by pointing out it was not C-130 transportable. He tried the same thing with strykers but failed because it IS C-130 transportable. Now we have a new "study" criticizing a program Rumsfeld wishes to kill. Surprise, surprise.
Strykers Get the Job Done
Tuesday, April 5, 2005; Page A22
I am with the 1st Battalion, 24th Infantry Regiment, which has operated in Mosul, Iraq, since last October with 75 Strykers.
A March 31 article ["Study Faults Army Vehicle," front page] cites the Stryker's substandard survivability and maintenance as putting soldiers' lives at risk. I strongly disagree.
Since October our battalion's Strykers have been engaged with 122 improvised explosive devices (IEDs), 186 rocket-propelled grenades (RPGs), 33 car bombs (10 of which were suicide car bombs) and much mortar and small-arms fire. In November and December, we fought as many as 70 insurgents during attacks. As a result, the battalion had seven soldiers killed in action and 102 wounded (81 of whom returned to duty within 21 days). Most casualties came during dismounted infantry operations.
The insurgents' most lethal weapon is the suicide car bomb. When these car bombs slam into Strykers, they create explosions that are equivalent to a 500-pound bomb. Yet in all 10 suicide car bomb attacks, no soldier on the Strykers was killed or lost a limb or eyesight.
During the past six months, one Stryker, C21, has been hit by a suicide car bomb, nine IEDs, eight RPG direct hits and a lot of small arms fire. Its crew had six wounded, but all of its soldiers are still in Iraq and fighting. After each attack, the Stryker either stayed in the fight or was repaired in less than 48 hours.
Not only is the Stryker survivable, it is reliable. Our 75 Strykers each have at least 20,000 miles on them. We average more than 1,000 miles a month, yet we have maintained, on average, a 96 percent operational readiness rate. That means that only three or four Strykers are down at any given time. This is the best operational readiness rate of any armored vehicle in the Army. We also average less than 24 hours to refit a vehicle after it has been damaged.
In urban combat, no better vehicle exists for delivering a squad of infantrymen to close in and destroy the enemy. The Stryker is fast, quiet, survivable, reliable and lethal. Most important, it delivers the most valuable weapon to the battlefield: a soldier.
MICHAEL E. KURILLA
1st Battalion, 24th Infantry Regiment
Stryker Brigade Combat Team