  We study the supersymmetry breaking induced by probe anti-D3-branes at the
tip of the Klebanov-Strassler throat geometry. Antibranes inside this geometry
polarize and can be described by an NS5-brane wrapping an $S^2$. When the
number of antibranes is small compared to the background flux a metastable
state exists that breaks supersymmetry. We present a manifestly supersymmetric
effective model that realizes the polarized metastable state as a solution,
spontaneously breaking the supersymmetry. The supersymmetric model relies
crucially on the inclusion of Kaluza-Klein (matrix) degrees of freedom on the
$S^2$ and two supersymmetric irrelevant deformations of ${\cal N}=4$
super-Yang-Mills (SYM), describing a large number of supersymmetric D3-branes
in the IR. We explicitly identify the massless Goldstino and compute the
spectrum of massive fluctuations around the metastable supersymmetry-breaking
minimum, finding a Kaluza-Klein tower with masses warped down from the string
scale. Below the Kaluza-Klein scale the massive tower can be integrated out and
supersymmetry is realized nonlinearly. We comment on the effect of the
Kaluza-Klein modes on the effective description of de Sitter vacua in string
theory and inflationary model building.
