Just to properly correct the above.
The actual rate you are paying is in the 14% range
It's just that for most of america they only see 1/2 of it because the employer pays the other half so it's hidden from immediate view (but still of course factors into salary and hiring calculations).
Now if you happen to be the one signing the checks or are self employed then you get to see the real number.
I'm sure the government does that on purpose as if everyone's paychecks started being the same but the original number was more and the taxes showed the full amount deducted, the sheep might start getting restless.
Just like if instead of having "withholding" and the government getting free loans, everyone in the country had to write a check on April 15th for their full taxes of the year to the government, probably April 16th would be the next revolution as folks decide to send them lead instead of checks.