Here is the short second amendment:
"A well regulated Militia, being necessary to the security of a free State, 
the right of the people to keep and bear Arms, shall not be infringed." 
A WELL REGULATED MILITIA for OUR Nations Security; 
with the RIGHT of those people to keep and bear arms 
shall not be infringed. 
It has nothing to do with mass shootings, 
nor civilians owning military assault weapons. 
As a firearms owner myself, 
I feel that anyone that owns a firearm should be will vetted 
and they should be held to a higher standard. 
Like the military is well regulated, 
those who own firearms should be well regulated. 
Let us: 
1. Close the loopholes at gun shows 
2. Make it harder for criminals to obtain firearms, 
by banning online gun kits
3. Have a buy back program for assault weapons 
AND
4. Expand background checks and vetting
Only then can we go forward like with Germany, Sweden, 
and New Zealand for example; and put a stop to mass shootings.
That is "My Two Cents" Second Amendment Edition.