If you need to ask why to join, you shouldn‘t. Joining the military is as erious commitment, physically, mentally and emotionally. You msut accept that you may be asked to sacrifice for your country, even to give your life. You must be willing to accept that what you do may lead directly or indirectly to the death of other human beings. You must also think every day about the country you‘re serving, and why, and never let yourself forget it. Every time you‘re out you shoudl looka roudn you and remind yourself that every bit of freedom we have in this world has been bought by the blood of the brave, anda sk yourself if you‘d be willing to make your own donation if the time came.
If you can decide after this that yes, it is for you, then the best of luck, and I hope to see you serving one day.