This two-part paper seeks to invite discussion on a deeply embedded narrative in the European scholarly and public discourse that reduces the protection of national constitutions to Eurosceptic, old-fashioned reluctance to relinquish sovereignty. The paper argues that because of the simplistic ‘Eurosceptic’-‘Euro-friendly’ looking glass, the discourse has broadly been oblivious of, and given scholarly legitimacy to, the erosion of a range of classic constitutional rights and rule of law safeguards in EU law. Part 1 of the paper, documenting comparative case law in seven areas, posits an emergence at the EU level of the adoption of measures which, if attempted at national level without the constraints of EU law, would in a significant number of national legal orders prompt constitutional courts to voice serious concerns about core European constitutional values. The case studies start with some past criticisms regarding rights protection in the single market, moving then to EU measures that have affected core constitutional values, such as secret anti-terrorist measures, the Data Retention Directive, the European Arrest Warrant system with its numerous Kafkaesque elements, the broader move towards imposition of criminal and administrative sanctions on the basis of teleological interpretation and without a law, and the ESM Treaty. The paper also queries the reduced access to courts, the changing role of courts and an emerging gap in constitutional review. Against this background, Part 2 of the paper calls for recalibrating the discourse towards ‘substantive co-operative constitutionalism’. The aim is to explore how to better uphold the standards of protection developed by national constitutional and supreme courts for classic, substantive constitutional values, in a context where EU constitutional law has brought about a shift towards a thin, weak, procedural version of constitutionalism, the rule of law and judicial review, with priority given to effectiveness, uniformity, trust and, after Melloni, supremacy over constitutional rights.