Tire Blowout problems of the 1997 Plymouth Grand Voyager

Vehicle is garage kept, and well maintained. Original tires with light to moderate treadwear. On clear dry well maintained toll road while on cruise control at 70 mph, the front left tire sidewall completely blew out. My wife (the driver) was fortunately able to keep the vehicle under control and make it to the shoulder. This could have been disastrous if she had not kept her head and not slammed on brakes or panicked and oversteered. We felt it necessary to replace the entire set of tires, even though the remaining tire's treadware seemed fine. We saved the pieces of the tire that blew, took digital pictures, and video. I question safety of the tire and large Mini-van matchup. Hopefully, should this happen to anyone else, they too are fortunate, as was my wife. (tiresize: p215/65r15)( dot number: tire size: p215/65r15 ).