The Itanium was dead before it appeared
The concept of the Itanium was wrong, even before you could actually buy a computer with an Itanium, IBM and DEC/Compaq already heavily criticized its design and architectural set up. And they were right. What people seem to forget is that this CPU was going to be the successor of the x86, if Intel would have had its way. It was only after AMD came with the 64 bit version of the x86 architecture that Intel was forced to go that way.
That incredible moron Mike Capellas destroyed the Alpha CPU, and replace it by the Itanium. Most likely to make Compaq a better marriage candidate for HP. Many of the Alpha's design features can be found in today's CPUs. Its memory access speed was still the fastest in the world, years after it went out of production. If HP would have used that CPU instead of the doomed Itanium, combined with Tru64 Unix, instead of that antiquated HP-UX, they still might have been a producer of high-end servers and operating systems.today, instead of just another x86 box producer.