Essentially yes. In it was written several catches that even slip our modern minds. It was written to protect the people for the greatest threat of all, and that is themselves. The Constitution was written with Polybius in mind who noticed that the customs of the people become corrupt (that's his language). Through this, freedom is lost and a nation is destroyed.
the constitution is a living breathin document that is always being perfected by our supreme court to keep pace with the times but the founding fathers were pretty damn smart in the construction of it
As evidenced by today's society, obviously not.
Not perfect, but definitely the best thing going. It's a governments' governor.