The Constitution is for the Blood line of it's in house Staffs ... the Gettysburg Address is for the people

We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.

Now the way I see it is …. the Constitution established in 1787, who so many have died to uphold … is not actually for the people in general .. but for the “WE” who WROTE the constitution … those who hold the governing offices as overseers of the constitution ..

Now the word “OURSELVES” plainly refers to those within the “self unity” … those within the three Groups of Staffs …

And the words “OUR POSTERITY” … plainly refers to the descendants of those within the three Groups of Staffs …

Posterity means;
1.  people in future (within the three Groups of Staffs): all future generations (within the three Groups of Staffs)
2.  all descendants (within the three Groups of Staffs): all of somebody’s descendants  

HERE is more input from other WikiAnswers contributors:
The U.S. Constitution is the work of several men, directly and indirectly. The three most notable persons whose work influenced the Constitution but who were not involved in its writing are Thomas Jefferson, John Adams and Thomas Paine.
(this could mean that the constitution was not even written for these men nor for any of their generations of people to follow)

Primary Author: James Madison (drafted the Virginia Plan). He is known as “The Father of the Constitution.” James Madison wrote the Constitution in 1787. The constitution wasn’t passed until 1788. HERE

And then it appears that On November 19, 1863 President Abraham Lincoln stood up for the people in the The Gettysburg Address which  Senator Charles Sumner commented on during President Abraham Lincoln’s eulogy June 1, 1865,…

It is this Gettysburg Address … that the Love for the people still can be felt …  as his speech actually refers to another set of fathers, the rightful fathers of the United States …..
different from the fathers of the constitution …

HERE …

Four score and seven years ago our fathers brought forth on this continent, a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.

Now we are engaged in a great civil war, testing whether that nation, or any nation so conceived and so dedicated, can long endure. We are met on a great battle-field of that war. We have come to dedicate a portion of that field, as a final resting place for those who here gave their lives that that nation might live. It is altogether fitting and proper that we should do this.

But, in a larger sense, we can not dedicate — we can not consecrate — we can not hallow — this ground. The brave men, living and dead, who struggled here, have consecrated it, far above our poor power to add or detract. The world will little note, nor long remember what we say here, but it can never forget what they did here. It is for us the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us — that from these honored dead we take increased devotion to that cause for which they gave the last full measure of devotion — that we here highly resolve that these dead shall not have died in vain — that this nation, under God, shall have a new birth of freedom — and that government of the people, by the people, for the people, shall not perish from the… HERE