Why the heck is the U.S. government spending untold millions on obnoxious pax security procedures when they are so easy to circumvent?

I just entered the U.S. after originating at an offshore point of origin located within a country which the U.S. government has deemed a "high security risk."

As I correctly predicted prior to departure, I was not asked to produce any I.D. when checking baggage at the airport or obtaining my boarding passes, and;

the only time my I.D. was checked at all was as I was boarding the inbound U.S. aircraft, and this was done hurredly at the gate during the general boarding process (how in the world are these people supposed to be able to gauge the validity of passports which may be from dozens of different countries in several various forms; all in the course of about 1 second).

During the entire journey, I only went through screening once (at my point of origin, in the "high security risk" country) where I wasn't required to submit to the shoe carnival, frottage formation, laptop breakage roulette, etc., etc., and the screening process seemed cursory, at best.

So, let's see, the U.S. government has spent millions building this elaborate air security "fortress," but any reasonably sophisiticated international traveller can effectively use the "unlocked back door or window" to avoid all the B.S. now associated with domestic air travel, which, in my analogy, would be the "well lit and highly-visible-from-the-road front entrance."

Look, I'm as concerned about terrorism as anyone, and believe that our country is at real risk from another attack. But it seems like the strategy and tactics being deployed are just incredibly idiotic.

What's the point spending all this money and seriously jacking around with the domestic air travel system if anyone with half a clue (and, say, 30 minutes to think about it) can figure out how to circumvent it by:

1) checking through baggage to the U.S. on commercial aircraft without I.D. from countries deemed to be especially at high risk; and

2) being able to obtain access to aircraft flying through U.S. airspace after being subjected to only a small fraction of the scrutiny which most of us endure on a daily basis.

In a world of limited resources, couldn't the millions of dollars being spent on the TSA-driven system be more effectively targeted and deployed?

Apologies for the rant, it's just that the present system seems so completely idiotic, wasteful and dangerous.

Granted, government spending is fundmentally political in nature, but obsessing about the manner in which prior attacks were carried out to the point when other vulnerabilities are completely ignored seems pretty reckless.