There are multiple parts to this.
1. The founding fathers never intended for the 14th to be used as a path to citizenship. Enshrining the right of paath to citizenship was NOT the purpose of the 14th. The main purpose of the 14th is stated in the latter half of the amendment. It is to clarify and prevent laws being passed by the states or other municipalities that would deprive a citizen of "privileges or immunities" that are granted to all U.S. Citizens. (oh wait concealed carry reciprocity anyone?)
That is the exact argument the left uses for citizens not having the right to possess guns. The real meaning of the 2nd amendment is in the first section. Interpreting the constitution to say what you want it to say is one thing that is wrong with this country. The constitution is what it say. Not, what you want it to say.