-Interest groups are significant.
This is not controversial.
-At least some Israelis have at least some influence in the US politics.
This is not controversial
-Pro-Israel lobby in the US significantly shapes the US foreign policy.
This is controversial and requires solid evidence. Just because lobbying is important and that israelis are lobbying, you can't infer that every single lobbyist is significant.
My contention is that, while it's possible to make claims like the second one, measuring specific interest group power and figuring out how powerful they are is pretty difficult(compare with specific political party influence/power, this is more straightforward)
This is not controversial.
-At least some Israelis have at least some influence in the US politics.
This is not controversial
-Pro-Israel lobby in the US significantly shapes the US foreign policy.
This is controversial and requires solid evidence. Just because lobbying is important and that israelis are lobbying, you can't infer that every single lobbyist is significant.
My contention is that, while it's possible to make claims like the second one, measuring specific interest group power and figuring out how powerful they are is pretty difficult(compare with specific political party influence/power, this is more straightforward)