There's an apt joke for this: Q: Why is suicide illegal? A: Destruction of government property.

Truth is - property and property rights are largely a convention that we agree upon, that convention is how state/government is created.

Remember that there is only one sovereign in every single country on this planet - king, despot, president, parliament or the people. Individual sovereignty is practically non-existent.

You don't own the land or your body. We just agreed to protect each other's freedoms and grant certain protected rights.