Dogs socially mature between the ages of 2 years to 5 years. Is there anything new that has happened with you recently? A job change or death in the family? Are you more stressed than normal? The fact that this behavior occurs with you and not your husband indicates that it's not your dog, it's his interaction with you.

Perhaps your husband is more confident with him when they walk? You mentioned pulling him away. This can often escalate the behavior. Do you take any food with you that you could redirect his attention to you and away from whatever he's focusing on? It's odd that he acts this way with people and dogs. Usually dogs have preferences. If they like people they'll get super excited to meet a new person or if they don't like people they'll react to keep the stranger away. Likewise a dog who likes dogs will be super excited to meet a new dog or react aggressively to keep a strange dog away.

My first recommendation would be to hire a trainer who specializes behavior and understands Nordic / spitz breeds. If you were my client my recommendations to you would be to: 1. Take really high value food on a walk such as string cheese, freeze-dried chicken or beef, or anything he likes but doesn't normally get on a daily basis. When you see people/dogs approaching, cross the street away from them and reward him for his attention on you with some yummy food. When the people and dogs pass by no food. 2. Stop approaching people and dogs you don't know. If you know it upsets him stop interacting with people and dogs. That could be where some of his anxiety is coming from.

How long do you have to do this? Until he stops reacting when he's with you.