Swallow the bomb

With all the expensive and extensive airplane screening technologies that are being installed why does everyone involved assume that a person willing to die in an airplane explosion won't swallow the bomb?

It would be easy to swallow the chemical ingredients to create a binary bomb in plastic bags along with the mechanism to activate their mixing.

The Israeli's know how to solve this problem.  Intelligent questioning of all suspicious people.

Unfortunately the Israeli approach won't work outside of Israel.  The Israeli approach requires very intelligent young non-union people willing to work 3-4 years in a boring job before moving on to something interesting.  No other country has enough such people in their labor pool.  Nothing will ever work, outside of Israel, if it requires many long-term intelligent employees.

So we are stuck with very thorough background checks on everyone who wants to fly, lifetime background checks that put people in categories from 1 to 4.  Some categories (2-4) are allowed to fly unhindered, others (1s) are only allowed after thorough examination (including x-rays).  A few more airplane bombings and we will be forced into this social stratification system.