Want this question answered?
The Preamble.
preamble
The Preamble
It is the introduction. But I wouldn't call it the "soul."
President Trump is quoting the phrase from the beginning of the Preamble to the Constitution.
ANSWER
Constitutionally Protected elected REPRESENTATIVE Republic
Constitution
Preamble
Before this question is answered, let's show everyone what the preamble to The United States Constitution says. "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." So, what does this do for The United States? Well, in all honesty, nothing. This is simply an introduction to the constitution and states the intention of the documentation and does not grant anyone any power. However, it can be interpreted in such a way that could help an argument in a legal dispute.
The delegates call for the constitutional convention because they realized we need a stronger national government.
The Introduction to the Declaration is The Preamble.