Cold fusion bombs
The point of cold fusion is that it's a mild reaction, happening at room temperature.
In other words, it's the opposite of what you'd use to make a bomb.
A fusion reaction is more powerful than a fission reaction, so, yeah, you could make a bomb with it. You'd just have less radioactive fallout contaminating the area.
The "cold" part only means you don't have to get the material super-hot to start the fusion reaction. It somehow can start at a lower temperature. But the fusion reaction is just as powerful as if it were a "hot" one.