Here is something that God cannot do - God cannot drive out an army that has iron chariots:
17 And Judah went with Simeon his brother, and they slew the Canaanites that inhabited Zephath, and utterly destroyed it. And the name of the city was called Hormah.
18 Also Judah took Gaza with the coast thereof, and Askelon with the coast thereof, and Ekron with the coast thereof.
19 And the LORD was with Judah; and he drave out the inhabitants of the mountain; but could not drive out the inhabitants of the valley, because they had chariots of iron.
20 And they gave Hebron unto Caleb, as Moses said: and he expelled thence the three sons of Anak.
21 And the children of Benjamin did not drive out the Jebusites that inhabited Jerusalem; but the Jebusites dwell with the children of Benjamin in Jerusalem unto this day.
Blessed be god and his bible!