As the midrash says, “כל דור שאינו נבנה בימיו מעלה עליו כאלו החריבו. מאי טעמא לפי שלא עשה תשובה”.
We see from here that the only thing stopping the Beis HaMikdash from being rebuilt is ourselves. Today this is obvious for all to see. If Klal Yisroel would want the Beis HaMikdash then it would be a reality. The truth is, though, that we don’t want the Beis HaMikdash. We don’t want the war that might be caused by such a move. This is true both for the frum and the Hilonim/mesoratim.
There is only one person in the Israeli political system who is trying to change this sad situation. Moshe Feiglin and his Zehut party want Klal Yisroel to want to build the Beis HaMikdash. Whether you agree with the premise of the Machon HaMikdash or not — that is, whether or not you think that there is any reason to prepare for building the Beis HaMikdash before Moshiach’s arrival – this is surely a worthy goal. To paraphrase the midrash, anyone who hasn’t prepared Klal Yisroel mentally for rebuilding the Mikdash, it is as if he destroyed it.
Not supporting Zehut is tantamount to destroying the Beis HaMikdash.
Another way of understanding the above midrash is that it is referring to teshuva for the sin of sinas chinam, which was the cause of the churban. Here, too, there is only one political party in Israel which is trying to remove the incredible sinas chinam which is still rampant among us, primarily between Haredim and Hilonim. Zehut is the only party where Haredim and Hilonim feel equally welcome and work together without any stigma whatsoever. Their plans for replacing the current status-quo are geared toward removing the main cause of friction between the various sectors of Klal Yisroel.
Once again we come back to the same equation: Not supporting Zehut is tantamount to destroying the Beis HaMikdash.