A recent article in New York magazine argued that the billionaire Sheldon Adelson is largely responsible for the Republican party’s current pro-Israel stance. David Bernstein objects:
[P]utting aside the question of whether GOP support for Israel is truly “unconditional and unquestioning,” [as the article states], the person most responsible for making support for Israel a core Republican issue is Osama bin Laden, with a supporting role played by Yasir Arafat. Gallup polls from the past 25 years show that Republicans were already leaning somewhat more in favor of Israel in early 2001 than were Democrats. . . . This reflected the increasingly strong influence of pro-Israel evangelicals and national-security hawks in the Republican party, on the one hand, and the hostility or ambivalence of what was once known as the “McGovernite” wing of the Democratic party, on the other.
But the difference in partisan attitudes accelerated after 9/11. Relative support for Israel unsurprisingly went up among both Democrats and Republicans. September 11 made Americans more sensitive to Israel’s terrorism-related security concerns, and Arafat’s decision to continue and accelerate the second intifada—replete with bus, café, and synagogue bombings—was hardly likely to endear the Palestinian cause to Americans after 9/11. But these factors had a greater influence on Republican opinion than on Democratic opinion. . . .
In short, you have a Republican party in which 80 percent of the grass-roots membership supports Israel, and a significant percentage of that 80 percent considers it a litmus-test issue. Meanwhile, the current Democratic administration has engaged in open rhetorical warfare against an Israeli government led by Benjamin Netanyahu, whom Democrats tend to loathe and Republicans tend to admire. Under those circumstances, . . . it’s really not possible . . . to imagine any scenario other than the GOP, and all its major presidential candidates, offering Israel strong support.
Read more on Washington Post: https://www.washingtonpost.com/news/volokh-conspiracy/wp/2015/09/09/sept-11-is-responsible-for-overwhelming-gop-support-for-israel-not-sheldon-adelson/