What can one say on a day such as this? Rav Zalman Melamed perhaps put it best (link):
"We must remember that we are in the midst of a struggle for our right to all of Eretz Yisrael, to Jerusalem in particular, and even more, for the Temple Mount, site of our Holy Temples."
"I request, my beloved students, that you deflect all the pain, anger and trauma to the right channels: Study more Torah, do more good deeds, adding merits that will bring our Redemption closer."
I was in the kosher supermarket with my wife on Sunday and was standing by the checkout where they have a display of little candies and things and I remember thinking (and saying to her afterwards) that Jews are being persecuted all over the world, and here our minds are on kosher Tic-Tacs.
I don't mean we should all take vows of prishus or anything like that. That's not going to happen. But we can do our best to empathize and be mishtatef b'tza'aran shel Yisrael. We can do our best to set aside more time for Torah, for tefilah, and for speaking out for the values we hold dear and for our people.
I can't find the link now, but there were two sites where you could contribute money that would go to the families of those killed. If someone has the link, pls send it to me and I can add it to this post bl"n.