This meant that the main problem is the lack of power Congress had. They couldn't really do anything as they couldn't resolve problems between states, tax the people, or do anything really as they had to get 9/13 states to agree to pass a law. Alexander Hamilton saw these flaws and decided to say this in order to point out how much Congress lacked power.
"The fundamental defect is a want [lack] of power in Congress.
This meant that it was useless to dwell on the past and try to point out why this happened. Alexander Hamilton probably said this because he saw others trying to point fingers at others instead of doing what they should have.
"It is hardly worth while to show in what this consists as it seems to be universally acknowledged, or to point out how it has happened"
This meant that all they could and had to do was fix the Articles of Confederation. Alexander Hamilton probably said this because no one was focused solely on a solution, everyone was instead focused on blaming others.