No.
No. A dishounourable discharge bars the serviceman/woman from re-enlisting.
No.
You may be able to. Check the reinlistment code on your DD214. You may have to wait 1 or more years before you will be permitted to re-enlist.
Gomer Pyle USMC - 1964 To Re-enlist or Not to Re-enlist 3-22 is rated/received certificates of: Australia:G
No, but the Soldier is to immediately be sent for a medical evaluation
To enlist in something again.
I'm a bit uncertain that a med. discharge would result in an RE1, but if you were discharged with an RE1 code, then you're eligible for reenlistment without the requirement of a waiver.
When it decides to retire or not to re-enlist.
yes! with a waiver
Yes of course you can.
Yes, your military 201 (personnel) file is open for review if you re-enlist. There is an "R Code" given upon discharge. This determines when and if you may re-enlist. If you are inelligible, you will be notified. If you are currently re-enlisted, and it is determined later that you were inelligible, you will be removed from service.