Sticky question

Here's something that has been bouncing around in my head lately.

At what point are elected officials (for instance members of the House of Representatives and the Senate) subjected to security clearance investigations?

And those people in positions that are given high level security clearances, how soon after they leave office are those clearances revoked?

Some may have security clearances but elected officials are not required to have security clearances (or investigation).
Some staffers, etc., can be appointed to have security clearances though.

Some security clearances may have an expiration but others do not have one (even if no longer employed in a position where one is needed).

This means that, let's say a congressman, can have quite an unsavory past (or is presently unsavory), and would not pass a security clearance, but can have their position via election. It has happened, where this type of person was a congressman, and I am sure it still does.

The president can revoke a security clearance if he/she feels the need to. Maybe certain "few" others can, as well, but I know the president can.

Just seems kind of odd to me that when I went into the service (Air Force Reserve), I had all kinds of investigations done on me because I was getting a top secret security clearance. Yet someone can simply run for a representative's or senator's position in the federal government, win it via popular election, and automatically get a security clearance with nothing done to look into whether that person could be a security risk.

And I'm pretty sure my top secret security clearance ended the minute I left the service too. I'm sure I couldn't just walk into the bunker at Andrews Air Force Base keeping tabs on Air Force One any longer.

Yet people leaving public office in the federal government then get jobs BECAUSE of this access they still retain.

Just doesn't make any sense to me, so maybe I am just missing something.

Yes, most military security clearances do end (immediately or up to a couple years) after leaving service.

It makes no sense, to me either, that elected officials do not have the requirement of having a security clearance/investigation and, yet, are privy to sensitive/secret info, etc.

Having a required security clearance, for elected officials, has come up but, thus far, has been either "voted down" or "benched" due to those who did/do not want this requirement to come to pass.
Politicians, etc., who brought up arguments, against it, that make no sense to me.
Maybe one reason could be because there may be some "dirt" that they don't want dug up (by honest agents).