score:9
One reason may be the size of the city.
The Freie Hansestadt Bremen has 661,000 inhabitants (including Bremen and Bremerhaven), Hamburg has 1.7 million inhabitants. Lübeck has only 213,000 inhabitants. There are also discussions to merge Bremen with Niedersachsen because of the size. So it would be strange if there would be a new smaller Bundesland. Maybe the allies had similar thoughts.
About the second part of your question: In 1956 there was an attempt to restore their status as an independent federal state; but the Bundesverfassungsgerichts decided in the Lübeck-Urteil (Lübeck-Adjustment, 5. December 1956) that Lübeck will not become its own country. So any new attempt would be useless.
Upvote:6
Actually there are political groups going in the opposite direction. There is a widespread agreement that 16 Länder are too many, but also widespread disagreement how to do it.
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