The withdrawal of the socialist left from government as a result of the cabinet crisis of May 1937 had clearly marked the beginning of a concerted attack on the Caballeristas' remaining power bases. The assault was mounted by a PSOE executive significantly strengthened by the verdict of the July 1937 national committee meeting and supported to the hilt by the PCE. The object of the attack was to silence Largo Caballero and his supporters, to exclude them and their disruptive influence from the political life of the Republic at war. It was to achieve this that the socialist left had been ousted from the PSOE's provincial federation in Valencia and from the leadership of the parliamentary party, on which, prior to July 1936, it had enjoyed majority control. The erosion of the Caballeristas' power base also meant reduced press access - which in itself accelerated the process of political disintegration. The loss ofAdelante was inevitable once the reformist socialists had regained control of the provincial executive in Valencia. But most damaging of all for the left socialists was their loss of control over UGT newspapers such as Claridad (Madrid), Las Noticias (Barcelona) and La Correspondencia de Valencia. It is the erosion of the Caballeristas' position within the union organisation, that supposed bastion of left socialism, which we must now consider. For, by the summer of 1937, the PSOE reformists' central target for attack had become the UGT's national executive itself.