When will Christ's Kingdom become a political/governmental kingdom?
Christ's Kingdom becomes a political/governmental kingdom when He leaves Heaven and brings the Heavenly Kingdom with Him to set up the earthly Kingdom, at which point He becomes King of Kings and Lord of Lords. It will then be a visible, viable, governmental, political kingdom, and His dominion will continue not only for a thousand years but into eternity.
Les explains that the Kingdom of His dear Son is presently a spiritual kingdom located in Heaven, where Grace Age believers have their citizenship and have been translated into it. But when God the Son leaves Heaven and brings the Heavenly Kingdom with Him to set up the earthly Kingdom, believers will be with Him. At that time, the Kingdom will become a visible, viable, governmental, political kingdom when He becomes King of Kings and Lord of Lords. Les notes that His dominion, when He enters the Kingdom, will not last only a thousand years as Revelation teaches, but will continue into eternity—an eternal, everlasting Kingdom that shall not pass away or be destroyed.