To what extent was the DECLINE OF AUSTRIA mainly responsible for the unification of Germany?

Development of Nationalism, faliure of revolutions, coal, iron and the Zollverein, Great Power rivalry, Bismarck's diplomacy and Prussian military power. 

• Austria's economy was stagnated and her military power declining. Her exclusion from the North German confederation meant that she lost support from the other Great Powers and also from the Catholic states in the South of Germany. Previous relations with Russia were strained due to conflicting interests over the Eastern Question and Britain wasn't willing to back Austria as she wanted Italy to unite to act as a buffer to French expansion, Germany would do the same. 
• Austia's military strength was reduced due to her economic stagnation. Territorial gains made from the Treaty of Vienna overstreched her resorces and crippled her economy. This was when Prussia was economically prosperous and her militaty was…