European stock markets experienced modest gains following a recent ruling by the U.S. Supreme Court, which brought a sense of relief regarding trade tensions. Notably, markets in Milan, Paris, Frankfurt, Madrid, and London all saw increases, but the overall sentiment remained cautious rather than celebratory.

The hesitance in the markets is attributed to several factors. U.S. President Trump has indicated that he has a backup plan ready, which includes various trade measures under specific sections aimed to address unfair trade practices, national security, balance of payments issues, and discrimination against U.S. exports. This reassurance from Trump has led to a measured response from investors who are wary of overreacting to this ruling. Furthermore, the European Union has highlighted the importance of understanding the details surrounding the ruling, which specifically applies to tariffs initiated under the International Emergency Economic Powers Act.

Overall, while there is satisfaction with the ruling, especially for sectors tied to 'Made in Italy', caution remains as market participants evaluate the broader implications of these trade policies and the potential for Trump's policies to create further uncertainties in international trade.

The stock markets' cautious optimism reflects a complex interplay of politics and economics, as investors remain attentive to forthcoming developments related to U.S. trade actions and their impact on European economies.