They are brave. They are selfless, And they are often coming home from the war zone changed.
The courageous men and women who are fighting the war on terror in places like Iraq and Afghanistan are increasingly returning home with wounds that can't be seen.
I recently met Jesse Frewerd, an Iraq war veteran who suffers from a traumatic brain injury and bi-polar.
Frewerd was injured by an improvised explosive device in Iraq. "The IED went off under our vehicle. There was shrapnel everywhere," Frewerd told me. "I smacked my head on the 50 caliber machine gun and it knocked me out."
Frewerd returned home with a traumatic brain injury and post-traumatic stress disorder.
He says the IED incident was not the only thing that contributed to his mental health issues. "Dealing with life and death on a daily basis weighs heavily on your psyche. Even if it doesn't affect you right away, it does down the road."
Experts say that constant stress load on increasingly long deployments is contributing to large numbers of mental health issues. And the numbers bear that out.
A recent survey found that 20% of veterans who served in Iraq or Afghanistan suffer from major depression or post-traumatic stress disorder. 19% of the vets in those two categories have experienced a traumatic brain injury.
And here is a sobering stat. Only 50% of returning vets who need mental health treatment receive those services. Sadly, the mental illness stigma still exists.
Frewerd tells me the stigma is so strong in the military because of a culture of personal sacrifice and self reliance. "We are a tough group that is used to not complaining and just getting things done," Frewerd says.
During this Mental Health Month I find myself thinking often about those men and women who fight for the rest of us and pay the price with invisible wounds.
They leave their friends and family and voluntarily march into battle. What they don't volunteer for are silent injuries they suffer as a result of their service.
That sacrifice is just one more reason to thank our soldiers, sailors and airmen.