To which "state" are you referring?

"Security of a free State"? That's a ridiculous oxymoron.

You can be free in spite of a State, but you will never find freedom because of a State.

The guys who wrote the Constitution and Bill of Rights were so deluded on some issues it's not even funny.

But, you could use a different meaning of "State" and be accurate.

Such as, if "state" were taken to mean "condition", rewording "the Security of a free State" as "to secure a state of Freedom"- as in:
"A well regulated Militia, being necessary to secure a state of Freedom, the right of the people to keep and bear Arms, shall not be infringed."

That is one state I can get behind.

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