How many military members actually see combat?

It really depends on the unit and location you deploy and the time frame. My SFOD-A saw a lot of combat and we had a mechanic attached to our team. He wasn't a Special Forces soldier, but the enemy does not discriminate by your MOS because they have no clue of it (unless you were Bowe Bergdahl). Support personnel sometimes leave the wire on missions in combat zones like Afghanistan, Syria, or Iraq, but also look at the 3rd Special Forces Group (Airborne) personnel that were ambushed in Niger, not all of them were SF, some were support. Support personnel often have infantry support, but they also don't due to unit requirements at the time of the mission's execution. If there aren't any infantry to use to escort, then those support personnel may be their own infantry.
We had other support personnel attached to us from time to time such as intelligence personnel, logistical personnel, and others. We even brought the chaplain out on a return from KAF to our FOB Ghekko (later named after my friend Thom Maholic). The military will send you where you are needed and at times you may have to move by ground from one location to another. I often did PSD missions from Bagram to Kabul in 2007 escorting people that were not combat arms and at any time those people could have been in ground combat which is why we rehearsed actions upon enemy contact before movement. Just about any MOS can find itself in a combat situation. In 2012, FOB Salerno was hit by a suicide truck bomb and then 10 attackers came in on foot wearing suicide vests. Sometimes, the combat comes to you and again, your MOS means squat, when it happens, you have to be ready to fight.

If you’re a Medic/ Doc in the infantry, you shoot, operate and communicate just as an 11B until one of your soldiers call for medic! 11B’s don’t operate outside the FOB without Doc!

I was in Iraq in 2009-2010, and while my job was working on a computer on a base, I did the job with rockets raining down all around me and once had insurgents who slipped onto the base under cover of darkness pass within a few yards of my position. They ran away because the QRF did a sweep.

Tell the truth, You don't need anything disturbing your conscious because you lied about something. Oorah !

Simply Amazing.

I am a retired Transportation Corp NCO and I definitely left the base when I was deployed. Through all modes of transportation, the equipment and supplies have to leave the Port of Debarkation. It is the 88M's that move that equipment and supplies to its destination. 88H's unload that equipment and 88N set up movement routes and monitor and man convoy checkpoints on those routes. No of these activities typically take place on on-post roads. In short TRANSPORTATION....TRANSPORTS...EQUIPMENT.

I am a retired Transportation Corp NCO and I definitely left the base when I was deployed. Through all modes of transportation, the equipment and supplies have to leave the Port of Debarkation. It is the 88M's that move that equipment and supplies to its destination. 88H's unload that equipment and 88N set up movement routes and monitor and man convoy checkpoints on those routes. No of these activities typically take place on on-post roads. In short TRANSPORTATION....TRANSPORTS...EQUIPMENT.

In regards to deploying, when I served I only knew two types of Marines: those who had been and those who were going. As far as those that would see close quarters combat, i.e. small arms and hand to hand, the number was limited.

I was an Air Defencer and I saw combat. Whole lot of us saw it. No such thing as sitting back and not seeing combat now.

I have been on four deployments. First one I never saw a thing. Second one was in Ramadi in 05-06. I saw more than I ever want to see again. The third and the fourth were just like the first. Nothing to write home about. Time and place and luck or lack of play a part as well.