Set aside the fact that States already have the power to form their own militias. Oklahoma's own laws already established the Oklahoma State Guard under the Oklahoma State Guard act of 1941. If anything we should be encouraging the battiest of the battiest to join up and take part in the lawful exercise of their rights.
By joining State militias they are less dangerous than they are today. Right now the big word in Domestic terrorism is "Lone wolf" indicating an individual or small group acting independently of the larger "Patriot" militia movement. By organizing and centralizing militia groups lose their ability to deny involvement in acts of domestic terrorism and the people in charge can be held politically responsible.
Then we are brought to why joining State Militias actually increases the leverage of the Federal Government in cases of insurrection or rebellion.
Title 10 of the United States Code deals with the Armed Forces of the United States. From the Army, Navy, Marines, Air Force, Guard and Reserve this part of the USC lays out the guidelines for their individual missions and responsibilities and their organizational structure. It also deals with the organization and authority of State sponsored militias. Now the Tea Partiers in Oklahoma seem to be suggesting setting up a Statewide militia for the State of Oklahoma. This would make that militia subject to Title 10.
Under Title 10 USC 332 – "Use of militia and armed forces to enforce Federal authority"
Whenever the President considers that unlawful obstructions, combinations, or assemblages, or rebellion against the authority of the United States, make it impracticable to enforce the laws of the United States in any State or Territory by the ordinary course of judicial proceedings, he may call into Federal service such of the militia of any State, and use such of the armed forces, as he considers necessary to enforce those laws or to suppress the rebellion.
And 10 USC 333 – "Interference with State and Federal law"
The President, by using the militia or the armed forces, or both, or by any other means, shall take such measures as he considers necessary to suppress, in a State, any insurrection, domestic violence, unlawful combination, or conspiracy, if it -
(1) so hinders the execution of the laws of that State, and of the United States within the State, that any part or class of its people is deprived of a right, privilege, immunity, or protection named in the Constitution and secured by law, and the constituted authorities of that State are unable, fail, or refuse to protect that right, privilege, or immunity, or to give that protection; or
(2) opposes or obstructs the execution of the laws of the United States or impedes the course of justice under those laws.
In any situation covered by clause (1), the State shall be considered to have denied the equal protection of the laws secured by the Constitution
The organization of these Tea Partiers into State Militias is much better than loosely aligned groups with no one to hold responsible. How many Governors are willing to risk their political careers by training militiamen who are gonna kill police officers? By integrating the new Militia movement into the State militias more oversight and control will take place.