Maybe this is why they had to take the land.
Exd 23:28 And I will send hornets before thee, which shall drive out the Hivite, the Canaanite, and the Hittite, from before thee.
Exd 23:29 I will not drive them out from before thee in one year; lest the land become desolate, and the beast of the field multiply against thee.
Exd 23:30 By little and little I will drive them out from before thee, until thou be increased, and inherit the land.
And then this happened....
Num 13:32 And they brought up an evil report of the land which they had searched unto the children of Israel, saying, The land, through which we have gone to search it, [is] a land that eateth up the inhabitants thereof; and all the people that we saw in it [are] men of a great stature.
Num 14:4 And they said one to another, Let us make a captain, and let us return into Egypt.
Num 14:8 If the LORD delight in us, then he will bring us into this land, and give it us; a land which floweth with milk and honey.
Num 14:9 Only rebel not ye against the LORD, neither fear ye the people of the land; for they [are] bread for us: their defence is departed from them, and the LORD [is] with us: fear them not.
Num 14:10 But all the congregation bade stone them with stones.....
Then 40 years later...
Num 32:7 And wherefore discourage ye the heart of the children of Israel from going over into the land which the LORD hath given them?
Num 32:8 Thus did your fathers, when I sent them from Kadeshbarnea to see the land.
Num 32:9 For when they went up unto the valley of Eshcol, and saw the land, they discouraged the heart of the children of Israel, that they should not go into the land which the LORD had given them.
Num 32:15 For if ye turn away from after him, he will yet again leave them in the wilderness; and ye shall destroy all this people.
And none of that changes the fact that God commanded the armies of Israel to go to battle many times rather than sending legions of angels to fight in their place. God usually expects us to do what we can and then works through those with the faith to take action. He does not want us continually looking to him to provide what we are perfectly capable of accomplishing ourselves.