Yes, it is true. If you want to make alot of money, consider becoming a Software Engineer with one of the many Defense Contractors in the Baltimore/Washington area. The golden ticket is your ability to obtain a Top Secret/SCI Full-scope with polygraph clearance. This is your Golden Ticket and will allow you to earn approximately $60k more a year than over a similar private sector position where you are competing with the H-1B Visa software programmers. This is what lowers what private companies are willing to pay you.
So, if you are clearable, start looking into working for a defense contractor. Note that not all contracting companies are the same. Contracting companies can be categorized as the following:
Big-Box Companies acting as the Prime on the contract.
Small subcontracting companies that sub to the primes.
Typically the Primes cannot staff the contracts they win, so they have partners that they allow to help staff the contracts as subcontractors.
Both Prime and subcontractors can be:
mere body shops or
'Butts-in-Seats' type companies.
'Butts-in-Seats' is where a company will hire anyone that has a active clearance and puts the new hire on contract as a billable Full-Time Engineer (FTE) regardless of qualifications. There is the typical 80/20 rule where 80% of the engineers on contract are not needed, are redundant or just plane do not work and watch YouTube or read Facebook all day.
The real bit of advice is to know someone that already works for one of these defense contractors and ask them about the company and contracts. I would steer clear of the larger 'big box' companies since you will not get paid well and you will be lost in the bureaucracy of a large corporation. Focus on the smaller companies. But be careful that they are not a 'butts'-in-seats' company that will place you on any contract and pay you as low as they can so they can pocket the difference. Be sure the company principals are billing. If they are on overhead, this means they need to take more money out of your hourly billable to pay for their existence.
Your day-to-day will require that you will work on site in government spaces. So, in effect, your company really becomes a payroll service since you do not sit in a company facility working with others in your company on a single product like an Apple or Google. In reality, you work in subpar government spaces with many different contractors and the government customer. You become assimilated into the government bureaucracy and processes. It is quite the experience and you lose a little bit of your soul each day.
So the key here is to choose a small company wisely, one where the principals are billable, empower you and are very transparent. A company where the team understands the game and understands that a good engineer wants to have fun and do great things at work -- not just sit at a desk billing. If the owners have Phds and tout their degrees, run away. These are folks that just do not get it and will waste your time as you try to create a better version of yourself. The one government agency I worked with was actually cutting all the PHd billet positions since they were deemed not essential. Once again proving the Software Engineer is the work horse of the defense contracting world.
So if you are able to get a security clearance, do not mind working in government spaces, and want to make alot of money, consider joining a small defense contracting company with the right ideology. I am being billed at $130/hour as a Principal Software Engineer. A DEVOPS coworker with a 2-year Associated degree is being paid $108/hour. Yes, America is great.
Do not use a recruiter to find you a position with a good defense contractor. They typical represent the body shop companies that do not pay well and have sub-par positions. Use Google to find small companies in your area. Send them an email with a cover letter on how you can bring value to their company. Small companies love eager, sincere and appreciative people and will go out of their way if they have a position that matches your goals.
Be forewarned, you will shake your head at all of the crap you have to deal with when working with the government and other contractors. Yes, you will learn from your team and it will make you a great and 'street smart' software engineer. In the end, it is all in what you define as being successful.
My definition of success is, Enjoying my work, supporting the mission, being challenged and being highly compensated for my hard work.