The lessons in this parsha that weigh on the war are staggering. This parsha speficially talks about our attitude about Eretz Yisrael. Moshe warns the nation not to fall into the trap and think that they have inherited the land due to their own efforts and merits. Do not forget Hashem took you out of Egypt, the manna, the wars you won were directed by God, etc. He warns they should remember Hashem and not say "Kochi V'Otzem Yadi" (8:17) - by the strength of my hand I have inherited the land.
Many times throughout the parsha Moshe mentions this idea again and again, and says you are inheriting not by your own rights. Hashem wanted to destroy you a number of times, when you did x, y and z in the desert. In 9:5 Moshe clearly says, "Not by your merits do you come to inherit the land, rather because of the wickedness of the other nations Hashem promised to your father Avraham, Isaac and Jacob, etc..."
In the current war we (our government) have been declaring such things as "We will dictate the terms of the peace" and "We will make them fear us" and other things of the sort. Clearly we have fallen into the trap Moshe warned us so strongly against in this weeks parsha.
If we would be more humble in our attitude and give Hashem some of the credit, he would look more kindly upon helping us out of our problems and helping us live here peacefully.. The parsha concludes with Moshe saying, "Nobody will be able to stand before you. Hashem will place on you fear and trembling in all the lands you will tread upon."
If we would do our part, He will do His.