Death lines (I–IV), detailed in the main text, in B–P space. When a source lies vertically above a given line, the model says that the star can “switch on” as a radio pulsar. Known radio-loud magnetars (namely, SGR J1745–2900, PSR J1622–4950, XTE J1810–197, 1E 1547.0–5408, SGR 1935+2154, and Swift J1818.0–1607) are shown by red stars, and a few high-B pulsars (PSR J1119–6127, PSR J1734–3333, and PSR J1718–3718) are shown with black diamonds. The primary in LSI is shown as a black star, with the dashed line delineating the possible B-field range.