Why did Israel lack weapons of war?

Judges 5:8 (ESV)

8 When new gods were chosen, then war was in the gates. Was shield or spear to be seen among forty thousand in Israel?

The Israelites needed to devote all their energies to maintaining their livelihood, so they lacked shields or spears needed to defend themselves. The lack of arms is rightfully interpreted as another symptom of the nation’s depressed condition, but in this context it represents another way of highlighting the role of Yahweh in the victory over the Canaanites. Like the earlier battle of Jericho, this battle will be won by God in spite of human inadequacy.1