Speaking for myself I would say IF this happens we can build another one God willing. If it was built once it can be built again it is the land that is holy.
Actions speak louder than words. The question is have they returned to sins?
Allah (swt) States: "And we decreed for the Children of Israel in the Scripture, that indeed you would do mischief on the earth twice and you will become tyrants and extremely arrogant! So, when the promise came for the first of the two, We sent against you slaves of Ours given to terrible warfare. They entered the very innermost parts of your homes. And it was a promise (completely) fulfilled. Then We gave you once again, a return of victory over them. And We helped you with wealth and children and made you more numerous in manpower. (And We said): 'If you do well, you do good for your ownselves, and if you do evil (you do it) against yourselves'. Then, when the second promise came to pass, (We permitted your enemies) to make your faces sorrowful and to enter the mosque (of Jerusalem) as they had entered it before, and to destroy with utter destruction all that fell in their hands. [And We Said in the Taurat (Torah)]:
'It may be that your Lord may show mercy unto you, but if you return (to sins), We shall return (to Our Punishment). And We have made Hell a prison for the disbelievers" [Qur'an 17:4-8].
“… Verily, the earth is Allaah’s. He gives it as a heritage to whom He wills of His slaves; and the (blessed) end is for the Muttaqoon (the pious).” [al-A’raaf 7:128]