Unnaturalness between the child and the parent; death, dearth, dissolutions of ancient amities; divisions in state, menaces and malediction against king and nobles; needless diffidences, banishment of friends, dissipation of cohorts, nuptial breaches, and I know not what. (King Lear, I.ii.120-123)
Each of these comes to pass, in some way or another, during the course of the play. Later on, Lear's fool adds to the list of woes: priests who do not practice what they preach, brewers who water down their beer, nobles practicing common occupations, people burned for expressing their sexuality, and many others besides. (King Lear, III.ii.76-89) Unlike Edmund's list of problems, the fulfillment of these is not specifically detailed in the text of the play, but this second catalogue adds to the general feeling of the dissolution of society that runs throughout the drama.
All of these problems can be traced (directly or indirectly) to Lear's abdication of the throne. Although Lear had no thought for the problems it might cause, the abandonment of the royal throne by the king had struck at the very heart of the social order that the Englishmen in Shakespeare's time had envisioned. The king was the representative of God on earth in the political arena. Since the Reformation in England, the King had also been the successor of the Pope as the head of the Church of England and, hence, God's representative on earth in the spiritual arena, as well. For Lear to abandon the throne and to divide his kingdom was for him to mock the divine order and the great chain of being to which Elizabethans likened their society.
Lear's fatal flaw is lack of insight; Regan claims early in the play that "he hath ever but slenderly known himself." (King Lear, I.i.286-287) Sight and insight are major themes in the play; many of the tragic situations could have been avoided if the characters had better understood themselves, their situation, or each other. Cordelia fails to see the ritual nature of the favor her father asks of her; Lear fails to see that his daughter, in refusing to participate in the test, is attempting to deal with him as a person, outside of the ritual framework in which he operates; Regan and Goneril fail to see Edmund's trickery; Gloucester, like Oedipus, gains insight only when he is blinded. It is difficult to blame the characters for not better seeing each other, however, when Shakespeare gives us so little character development in the plot. This lack of character makes the play seem more like an allegory or a fable than one of Shakespeare's other tragedies, where the character development is so rich. (King Lear is poorly developed compared to, say, Richard III or Hamlet.)
If Lear had had more insight, he would have seen the way in which he threatened the stability of the social structure. When he forsakes the throne and divides his country, this stability is left without anything at the top to hold it together, and forces that had been kept in check are let run wild: the lustful ambition of Regan and Goneril, the violent ambition of the bastard Edmund, and even the violent abandon of the elements in the heavens. The good Earl of Kent is banished, Cordelia is stripped of her dowry and taken away to France, and Edgar, Gloucester's good son, is proclaimed an outlaw. Evil is loosed on the country and good is pushed away. The fool disappears because everyone in the kingdom becomes foolish; as with virtue, there is no room for wisdom in a country without a social order, and that requires a monarch.
All of these elements had been held in check by the office of the king, which was bigger than any man who might fill it. By retiring, Lear directly attacked the authority of the office, and weakened the authority on which the entire social order rested. His withdrawal from the political process created a country in which the good are afraid to live up to their potential and the evil run amok. As the bastard Edmund explains to a soldier upon ordering the death of Lear and Cordelia,
Know thou this, that men
Are as the time is. To be tender-minded
Does not become a sword. Thy great employment
Will not bear question. (King Lear, V.iii.31-34)
Lear's central flaw, lack of insight, is aided and abetted in the violence it does to the social system by pride and stubbornness. His fool constantly reminds him of this fact before disappearing after act III. Lear stubbornly attempts to hold on to what he has given away, as when his daughters try to persuade him to reduce the number of knights that he keeps in his retinue in II.iv; he proudly refuses to hear Kent's voice of reason after stripping Cordelia of her inheritance. Although the other characters have faults of their own, these faults are of lesser importance than the monarch's, as his office had held the faults of the other characters in check while he held the office.
It seems likely that King Lear was intended, at least in part, as a warning to the new English monarch, King James I, who assumed the throne in 1603, after the death of Elizabeth. (The play was written some time between 1603 and 1606, and was performed as the court's Christmas celebrations in 1606.) James was, in some ways, like Lear: He enjoyed hunting; ran a court frequently thought to be corrupt, especially because of his extensive grants of monopolies and his difficulties reconciling the various Protestant ways of thinking in the kingdom; and insisted on monarchical absolutist prerogatives. James also had plans for unifying England and Scotland, and the play's theme of the dangers of division of land may resonate with this. (Introduction 889)
In the end, however, the play is carried and made compelling by the larger-than-life drama which operates beyond any particular political situation in Shakespeare's contemporary world. The dramatic interaction of characters whose motivations are shrouded add a mythic quality to the actions of the play that only accentuates the wrong that Lear does to his society. In this context, the expulsion of the good Kent from England seems almost a reversal of the expulsion of Adam and Eve from paradise, for instance. The veiled characters make the play understandable and captivating to audiences of any era.