Welcome to What Matters Now, a weekly podcast exploration into one key issue shaping Israel and the Jewish World — right now.

On Thursday this week, tens of thousands of marchers -- including several government ministers and MKs -- marked the 1967 reunification of Jerusalem under Israeli sovereignty with participation in the annual Flag March.

While most of the masses sang, danced, and yes, caused a ruckus through the Old City’s Muslim Quarter, much like every year in the recent past, at times parts of the mostly under-30, largely male crowd acted like a tinderbox eager for a spark.

What was different this year is a group of left-wing activists blocked a main artery from the West Bank bloc of Gush Etzion to prevent marchers from reaching the capital. Perhaps taking a page out of the judicial overhaul protests, they stood with massive banners, chanting, "Fascism will not pass; the marchers will not pass."

This push-pull political situation in Israel is the stuff scholars of contemporary history dream of. And for Dr. Sara Hirschhorn, an American historian and public intellectual who focuses on the Israeli ultranationalist movement, a research visit to the Holy Land couldn’t have been better timed.

Hirschhorn is currently an inaugural fellow at the Anti-Defamation League (ADL) Center for Antisemitism Research and an instructor in Jewish and Israel Studies at Rutgers University. In addition to her research into Israeli extremism, she also focuses on Diaspora-Israel relations and the Israeli-Palestinian Conflict.

Her first, award-winning book, "City on a Hilltop: American Jews and the Israeli Settler Movement" (Harvard, 2017) will soon be followed up on with an in-progress manuscript entitled "New Day in Babylon and Jerusalem: Zionism, Jewish Power, and Identity Politics Since 1967."We sat together this week and in our wide-ranging conversation, we discuss the increasing extremist symbolism of the Jerusalem Day Flag March. We also drill down on how Israel’s far-right parties are now considered mainstream as part of the Knesset coalition.

And, we discuss how by simply envisioning what the world could look like the day after peace breaks out, we may actually get there.

This week we ask Dr. Sara Hirschhorn, What Matters Now.

What Matters Now podcasts are available for download on iTunes, TuneIn, Pocket Casts, Stitcher, PlayerFM or wherever you get your podcasts.

IMAGE: Dr. Sara Hirschhorn in the Nomi Studios in Jerusalem. (Amanda Borschel-Dan/Times of Israel)