If someone is not randomly selected for screening, they can take weapons into the airport. The US has a single point of screening, which is burdened with the "we don't profile" excuse of randomness that makes it less effective than the Israeli method of screening with behavior profiling, regardless of ethnicity or citizenship. The US is larger and has a more diverse ethnicity and citizenry of travelers, true; but Israel has a larger problem with attempts to bypass their security than the US, and their security procedures for flight safety are more effective *and* less intrusive.
I don't understand how the specifics of the Israeli security solution that has evolved to what it is today is considered to be something of no value to a US system, regardless of its roots. It also doesn't rationalize the ineffectiveness of the US system represented by these scanners and enhanced pat-downs, so the scale of a nation's size is support of taking those extra steps rather than finding fault with them just because they're not made in America.
Having everybody go thru more advanced scanners will only be possible if said scanners do not pose a greater health risk of slowly killing everyone who boards a plane (or enters an airport) than the chances of quickly killing a few who fly. I'm sure that if such a scanner existed both the Israeli and US airports would want to use them. My point is that in the US it seems that only those would be used (along with other mostly limited procedures you mention) whereas in Israel and other countries they'd be supplemental to other more efficient *and* effective measures.
This whole "we fear more because we are greater" mentality is what allows ineffective and invasive actions by the US government to evolve into degradation of civil and human rights that we are witnessing today. Yes, the scanners are in the news more than the effective screening methods; because they are humiliating and degrading to our citizenry and to people in general while at the same time being arguably ineffective, hazardous, and suspect of a hidden agenda for profit and/or limits to freedom.