In Amalgamated Clothing Workers v. Richman Brothers Co., 348 U.S. 511, 75 S.Ct. 452, 99 L.Ed. 600 (1955), where a union, arguing that the field of interstate labor relations had been preempted by Congress, sued in federal court to enjoin an employer from seeking an injunction in a state court against peaceful picketing on the ground that such picketing still violated the state laws against conspiracy and restraint of trade, the Court held that neither the first nor the second explicit exception incorporated in 2283 of the Judicial Code would allow such a restraint of a state proceeding, for no federal labor statute expressly authorized injunction against a state court in such a situation and the federal court could not 'aid its jurisdiction' since it had as yet acquired none over the dispute and would not acquire any unless the N.L.R.B. brought an appropriate action; the here critical final phrase of 2283 was not there at issue since there had been no previous federal judgment to protect. However, the majority, in an opinion also written by Mr. Justice Frankfurter-and concurred in by Mr. Justice Reed, did say: 'We need not re-examine the series of decisions, prior to the enactment of Title 28 of the United States Code in 1948, which appeared to recognize implied exceptions to the historic prohibition against federal interference with state judicial proceedings. See Toucey v. New York Life Ins. Co., 314 U.S. 118, 62 S.Ct. 139, 86 L.Ed. 100. By that enactment, Congress made clear beyond cavil that the prohibition is not to be whittled away by judicial improvisation. The 1948 enactment revised as well as codified. The old section was thus embodied in the new 2283: .' (348 U.S. at page 514, 75 S.Ct. at page 454.) 'This is not a statute conveying a broad general policy for appropriate ad hoc application. Legislative policy is here expressed in a clear-cut prohibition qualified only by specifically defined exceptions.' 348 U.S. at pages 515-516, 75 S.Ct. at page 455. and in a footnote, commenting on the final paragraph of the Reviser's Note quoted above: 'Even if taken to mean that, despite the revised wording, the section is to derive its content from decisions prior to 1948, these contain no precedent for the present proceeding. Moreover, in context it is clear that the quoted phrase refers only to the particular problem which was before the Court in the Toucey case.' (348 U.S. at page 515 fn. 1, 75 S.Ct. at page 455.)