Actually, everything before the comma is a "phrase", Jim, and some sort of ablative expression from the Latin altho understood as a clause as in the paraphrase "It has come to our notice that a well-regulated militia is a good safeguard of our freedoms, and thus we find that the R to K&B shall not be infringed." After the comma comes a bunch of words that indeed is a clause as it has both subject and predicate and it is also the dependent or qualified clause. Whether or no the right to K&B is an individual right and unimpeachable in cases where its maintenance may not favor the state or the PTB is certainly up for grabs given that "a well-reguated militia is a collectivity. You'll wind up on the loosing end of this argument and I wouldn't be surprised if the occasion was another terrorist score and the presiding administration nominally "conservative" and possibly Republican. Who ya gonna call {names}, then, buddy?

jack