In Macbeth, how does unrestrained ambition destroy Macbeth's devotion to his country? Please provide and explain a specific example.
In the Elizabethan world of the Chain of Being, Macbeth's "vaulting ambition" that drives him to regicide leads to cosmic chaos as he murders a semi-divine monarch at the head of the hierarchical ordering of human life. With this world order destroyed, then, Scotland is thrown into disorder and "nothing is what is not." Moreover,with Macbeth's murder of Duncan, he leaps over time pushing the prophesy of the three witches ahead, fulfilling it. Thus, Macbeth assumes what Harold Bloom calls "a proleptic imagination" as he attempts to advance events and murder the future. For, even before he murders the king in his "black and deep desires" (1.4), Macbeth refers to himself as the royal "we," apparently in anticipation of his regal destiny.
Furthermore, Macbeth's proleptic mind propels him to murder the future in his slaying of Banquo, to whom the witches have prophesied that his sons will be kings. So, rather than being the victor for Scotland as he has been in his early battle with Macdonwald, he becomes his country's enemy as a tyrant who must be deposed. In Act V, Scene 2, the Scottish noblemen prepare to battle Macbeth:
MENTEITH What does the tyrant?
CAITHNESS Great Dunsinane he strongly fortifies.
Some say he's mad....
He cannot buckle his distempered cause
Within the belt of rule.
ANGUS ...Those he commands move only in command,
....Now does he feel his title
Hang loose... like a giant's robe....(5.2.12-19)
Further, Caithness prepares to march forward and kill Macbeth in order to save Scotland:
CAITHNESS Meet we themed'cine of the sickly weal,
And with him pour we, in country's purge (5.2.28-29)
Thus, in Macbeth's "vaulting ambition" he has leapt over time, murdering the future, abandoning his devotion of Scotland, and bringing himself to an empty life, "signifying nothing."