Complex sentence: Despite these preparations, the capital was seemingly within striking distance of German "panzers" and was targeted in massive air raids, although these raids caused only limited damage because of extensive anti-aircraft defenses and effective civilian fire brigades.
Split into simpler sentences: Despite these preparations, the capital was within striking distance of German "panzers" with the Luftwaffe mounting massive air raids on the city. The air raids caused only limited damage because of extensive anti-aircraft defenses and effective civilian fire brigades.