Senators vote, they don't lead people. To be a proven leader , you have to have directed people, given orders. You have to have been an executive.to have done these things.
There are many with leadership abilities who have not been executives.
Fred's experience has proven him competent, capable, pertained to issues of national security and left those whom he served satisfied and with a sense of respect for his service.
Huckabee's executive experience was riddled with ethics scandals, a ridiculous number of clemencies that went against the advice and best interest of others in his state, showed a propensity for taking "gifts" in lieu of favors, and left the conservatives in Arkansas with tatters for a movement after his betrayal of them after taking office.
No matter the platform for experience, it matters most what the individual does with his opportunity. I submit Fred Thompson has shown himself better at executing his responsibilities than Huckabee. Mike's executive position simply proved him to be wanting.
You obviously have NO idea what leadership actually is, and have horribly confused it with administration or management.
Leading people does NOT mean directing them or giving them orders.
Leadership does not require command, but leadership ALWAYS involves example and devotion. If you do not understand what leadership is, you have no chance of recognizing it when you see it.