If I'm not mistaken, Israel currently has a "Nationality Law" (aka Loyalty Law) that prohibits individuals with dual citizenship from being Knesset members. In order to have Israeli citizenship one has to swear to be loyal to Israel first.
Since the 40 members of the US Senate & and House(1) now have Israeli citizenship, they have sworn to be loyal to Israel first.
Unfortunately, not only US Senators & Congressmen are policy makers whose first loyalty it to Israel.(2)
Because so many of America's politicians & policy makers are Zionist "Israel Firsters" I think that it is unlikely that we will see any essentially necessary initiative to
expel these ethically compromised individuals from office to make way for policy makers whose loyalty is to America's best interest first.
(1) "U.S. SENATORS & CONGRESSMEN WITH DUAL CITIZENSHIP WITH ISRAEL"
http://www.informationclearinghouse.info/dual-citizens-israel-congress.jpg
(2) "Members in US politics who hold dual US/Israeli citizenship: (2013)"
Members in US politics who hold dual US/Israeli citizenship: – InvestmentWatch