Are you guys nuts. Tobirama is just careful, how long was the war between them. Would you trust a guy that was your enemy yesterday? Tobirama doesn't know shit about the Uchiha, so he doesn't trust them. I get that. They are living right beside the ones you hold dear most (family, friends etc). So he is a little uneasy, hell so would I. I don't think Tobirama is a bad guy, but he certanly has a shitty timing for his conversations.