Ideals of operators on $(oplus ell^infty(n))_{ell^1}$

The unique maximal ideal in the Banach algebra $L(E)$, $E = (oplus ell^infty(n))_{ell^1}$, is identified. The proof relies on techniques developed by Laustsen, Loy and Read and a dichotomy result for operators mapping into $L^1$ due to Laustsen, Odell, Schlumprecht and Zs{a}k.