One more area where you get a better deal in the US.
Military retirement pay in the US is never reduced by any other pension program that you are in. If you do go to work for the Federal government, as soon as you complete one year of actual service, you are credited with all of the time that you spent in the military, meaning that you are treated as if you had actually worked for the government for 21 (or more) years. This means, if layoffs occur, you are protected by your longevity.
When you retire from the civil service, you will receive a Civil Service pension and your full military retirement pay. The ONLY program that is reduced in the US is if you are drawing Social Security Retirement benefits and a Civil Service pension. Then, there is a reduction in your civil service pension, but only a portion of it is taken.
Retirement from corporations/companies has absolutely no effect on military retirement or Social Security. I personally know people that draw the maximum from Social Security, draw a very large pension from their work, and they get well in excess of $100,000 a year. That of course does not count any investment income, savings, etc.
Retiring early in the US permanently reduces your monthly Social Security and Pension income from most companies (and from the Civil Service). There is no "bridge" involved.