My (30/f) husband (36/m) bought a poster tube without asking me first.

I've been doing a lot of work with my therapist to make my house feel more comfortable to me. It’s a work in progress, but I've been getting rid of a lot of stuff. I'm currently working on my bedroom which has been my biggest challenge so far. I just got a small dresser and a night table. It still has a lot of work but it's coming along. Last night my husband who never really goes in the bedroom came in to show me something he bought. He had a poster tube and I asked him what it was for. He said he was going to hang up a poster of a band on the wall. I was immediately irate. I told him no. I said I didn't want anything on the wall. He said he would. I said that I don't want anything on the walls because that's how clutter starts. He said, "Well, then it's just clutter. It's a poster." I said it starts with a poster and then it just gets worse. He said he was going to hang it up anyway. I said no. He said he didn't understand why it was such a big deal. He said that he would hang it in any room he wanted and that I couldn't stop him. I let it go and went to bed thinking he didn't actually buy the poster and was just trying to upset me. This morning I’m going through the mail and there’s the poster. I’m irate. I’m boiling. I’m too angry to even think straight. I don't know if I should throw it away, leave it on the ground, or give it to him right away. I'm just so mad.