In the late 1960s, the economic historian Nathaniel Leff began publishing articles explaining why, since the 19th century, Brazil had exhibited slow economic growth and wide discrepancies between rich and poor. His explanations upended what was then, and largely remains, the widely held consensus of Brazilian economists. A devout Orthodox Jew who spent most of his career as a professor at Columbia University, Leff abruptly disappeared from view in the 1990s. Rafael Cariello explains the significance of Leff’s work, recounts his biography, and describes his own personal quest to discover the economist’s fate:

In his scholarly writings, Leff argues that the key to understanding why Brazil became a relatively poor country, with per-capita income far below the levels reached by Europe and the United States, was to be found in the 19th century—no earlier, no later. [By contrast], traditional historiography, which had produced the (still-dominant) narrative about the reasons for the country’s “backwardness,” tended to identify the colonial period [which ended in 1822] and the relationships between Portuguese America and the capitals of Europe as the source of the country’s sluggish pace toward industrialization and development. . . .

For Leff, the causes of Brazil’s underdevelopment also lay in the difficulty that the domestic market faced in articulating itself and growing more quickly, thus creating a complex economy. But instead of pointing the finger at commercial relationships with Europe, he blamed the Brazilian economy’s lack of internal integration—and the high cost of transportation in the country. . . .

As for Leff’s personal story, it tells much about the integration of Jews into American universities. Leff entered Harvard in the 1950s, when Ivy League schools were not entirely comfortable places for Jews. By the time he retired from Columbia, much had changed, as Cariello writes:

[One former colleague recalled Leff] coming to the campus and walking through the gardens and neoclassical buildings at Columbia in a dark hat and coat, with a full white beard. . . . [But in] the small photograph on the diplomatic document authorizing his entry into [Brazil, where he went to conduct research in 1963], Leff shows none of the features commonly associated with religious Jews. Not a hint of a beard, and no kippah. I put this to [his son] Avraham.

“Yes, it makes sense,” he said. “A while ago I was looking at my father’s reunion picture and a picture of him at Harvard. Had I not been told that was my father, I wouldn’t have known. He was totally clean-shaven, no hat, no nothing. This was America in the 1950s, where you didn’t rock the boat if you didn’t have to.” According to his son, Leff let his beard grow out only after he got tenure.

On Tuesday, a Hizballah drone attack injured three people in northern Israel. The next day, another attack, targeting an IDF base, injured eighteen people, six of them seriously, in Arab al-Amshe, also in the north. This second attack involved the simultaneous use of drones carrying explosives and guided antitank missiles. In both cases, the defensive systems that performed so successfully last weekend failed to stop the drones and missiles. Ron Ben-Yishai has a straightforward explanation as to why: the Lebanon-backed terrorist group is getting better at evading Israel defenses. He explains the three basis systems used to pilot these unmanned aircraft, and their practical effects:

These systems allow drones to act similarly to fighter jets, using “dead zones”—areas not visible to radar or other optical detection—to approach targets. They fly low initially, then ascend just before crashing and detonating on the target. The terrain of southern Lebanon is particularly conducive to such attacks.

But this requires skills that the terror group has honed over months of fighting against Israel. The latest attacks involved a large drone capable of carrying over 50 kg (110 lbs.) of explosives. The terrorists have likely analyzed Israel’s alert and interception systems, recognizing that shooting down their drones requires early detection to allow sufficient time for launching interceptors.

The IDF tries to detect any incoming drones on its radar, as it had done prior to the war. Despite Hizballah’s learning curve, the IDF’s technological edge offers an advantage. However, the military must recognize that any measure it takes is quickly observed and analyzed, and even the most effective defenses can be incomplete. The terrain near the Lebanon-Israel border continues to pose a challenge, necessitating technological solutions and significant financial investment.