It is quite well known that for any polyhedral set $K$ and any linear mapping $A$, the set $AK$ is polyhedral and hence closed. I am more curious about the converse problem, namely:
Suppose $K$ is a closed convex cone and for any linear mapping $A$, the set $AK$ is closed. Is $K$ a polyhedral cone?
For closed convex set, counterexample is easy to construct, e.g., $\{(x,y):y\geq x^2\}$. But for closed convex cone, I didn't find any easy counterexample.