These places are holy and revered throughout the Islamic world, surpassed only by those in Medina and Mecca.
To appreciate the fact and to view the sheer architectural beauty of these places, do a google search for Karbela/ Karbala or the ali/Najah mosque. You will see the beauty and can develop an appreciation for what roused the populace to hit the streets.
What would be in your estimation those locations within the United States you would deem sacred?
"These places are holy and revered throughout the Islamic world, surpassed only by those in Medina and Mecca."
This is because Christians do not (or should not) worship places but God alone. Anything else would be the same as worshipping the "creation" instead of the "Creator".
God decreed that we shall not make for ourselves gods or images made of wood, stone or metals in so many words, more or less. Even in creating altars for sacrifice, the stones were to be untouched by tools.
The Kingodom of Good is within us and we can worship God anywhere. We don't have to revere places with "God slept here" or 'Jesus walked here" or "Jesus ate here" with reverence. I can't go to the "Holy Land", but I have as much of the "Triune God" right here as I would retracing Jesus steps.