Question: Mark Zuckerberg said, "Our mission has, really, always been to connect the world."

My questions is: 
Can we say "Our mission ***is,*** really, always to connect the world"?

What's the difference between "has always been" and "is always" in this context?

Thank you for your help!

Answer: 
"has always been" means that the mission was always like this in the past.

"is always" is less emphatic about the past, and stresses the current and future mission.

If the mission were actually changing significantly, this could be made even clearer by saying "is now".
When you use: "has....to connect"
it means their mission is trying continuously to connect the world.
On the other hand,when you use:"is.....to connect"
it means their mission is made up to connect the world.