So here is an answer. This, as should be well understood by now, was completely un-necessary. Seemingly, David was not a threat to Absalom. David had resolved to leave his destiny in the hands of his God. Along with that, and based on the mournful response that David makes when he eventually (after the unfolding of the events to come) receives word of Absalom having been struck down and killed, one can even imagine that David asked for his God’s blessing and favor to fall upon the one whom He (God) had seen fit to place in the role of king, having given him favor with the people of that God.
No, David did not and could not have seen himself as being unlawfully or unjustly removed from the throne of Israel; and if he truly was the man after the Creator God’s own heart, and if he truly served under a special anointing of that God, it would have been incumbent upon him to seek and to serve his God’s will, even if that meant that he was not to be the king. Based on what he had done and had not done, as he delivered oppression and usurped justice (with morality-related mistakes to which fallen humans are prone as secondary issues), David would have been justified in believing in this way and acting accordingly.
Hushai, the one that had sent back to Jerusalem by David to serve as a “double-agent” in Absalom’s court, suggested a different strategy than that of Ahithophel. He reminded Absalom of the fact that his father was, most certainly, a warrior, and that the men with him were quite brave (2 Samuel 17:10). In that light, he suggests that “all Israel from Dan to Beer Sheba---in number like the sand of the sea!---be mustered to you, and you lead them personally into battle” (17:11b).
How interesting it is that Hushai just happens to toss in, almost as an aside, a description of the people of Israel as being as numerous as the sand on the seashore. In his advice to Absalom, which was really part of his service to David, he invokes the memory of the covenant promise that Israel’s God had originally made to Abraham. It is probably this, more than anything else that he said, that inspires Absalom to be partial to Hushai’s advice. After all, what proud, self-respecting Israelite would not be moved to act when regaled with such speech, as the person on the receiving end of such words would now be connected with the great patriarchal father?
Hushai adds: “We will come against him wherever he happens to be found. We will descend on him like the dew falls on the ground. Neither he nor any of the men who are with him will be spared alive---not one of them! If he regroups in a city, all Israel will take up ropes to that city and drag it down to the valley, so that not a single pebble will be left there!” (17:12-13) Hushai is definitely engaging in some pronounced hyperbole here. Though he does not believe or desire that such things will happen, he uses terms such as “All Israel,” and in reference to those with David, says that “not one of them” will be spared. These things are quite unlikely, yet for some reason they are appealing to Absalom. “Absalom and all the men of Israel said, ‘The advice of Hushai the Arkite sounds better than the advice of Ahithophel” (17:14a). So Absalom is heeding advice that is directed towards attacking and killing his father and his father’s men. This becomes his fatal mistake.
Following the report of the favorable response to Hushai’s advice, the author adds what is obviously a retroactive application of what was ultimately manifested as Divine displeasure with Absalom, no doubt because of the course of action that was now going to be undertaken, saying “the Lord had decided to frustrate the sound advice of Ahithophel, so that the Lord could bring disaster upon Absalom” (17:14b). This is the first negative connotation that one can find, from either the Lord of Israel or from man, in the story of Absalom’s insurrection and coming to power. To this point, Absalom could very well lay claim to being a leader and deliverer for Israel in the mold of Moses.