Tang Dynasty rules over and unified China because

They had a strong army that defended the borders and repal invaders.

They had a strong army that could defend the borders and repel invaders.

Explanation:

in 'popular history' of europe in america it's common to blame the rise of the nazis (and of coursewwii, too) mainly on the treaty of versailles. despite the harshness of the treaty and despite the inflation of 1919-23 germany did benefit from the economic buoyancy of the roaring twenties. in the general election in 1928, the nazis only managed to get 12 (out of about 584) seats in the reichstag. the nazis were widely seen as a laughing-stock led by a funny little man given to yelling and wild gesticulation. of all european countries, none was hit harder than germany by the stockmarket crash of october 1929. germany had borrowed very large sums from american banks, with much of the money repayable either on demand or at short notice. these loans were of course recalled, and bankruptcies in germany rose sharply from the start of 1930 (or earlier). unemployment rose sharply, too. the german constitution of 1919 contained much that was utopian, including the right to paid employment. the realities of the situation made a mockery of the weimar constitution. one of german's great weaknesses at the time was the lack of a broadly based, popular right-wing party comparable to, say, the republicans in the us or the conservatives in britain. the obvious candidate, the german nationalists (the dnvp), had lost its grip and was hopelessly out oftouch with many of its supporters especially in rural areas. germany became increasingly hard to govern.

from about the middle of 1930 onwards the new chancellor, br�ning, had to govern by decree. in the absence of mainstream right-wing party, the nazis - who ruthlessly exploited genuine grievances - suddenly became the largest single party in the reichstag. with the growing effects of the great depression, unemployment reached about 27% (or more) in 1932. acting on bad advice (from the dnvp) hindenburg dismissed brüning in july 1932. in the general election that followed, the nazis won 37% of the seats. the other party that did well was the communist party (kpd) with 14%. fresh elections were held in november 1932: the nazi vote fell slightly, but the communist vote rose to 17%. in the streets of berlin and other major cities violence between left and right and their paramilitary wings grew. by late 1932, the effects of the great depression in germany had passed their peak, but this wasn't obvious at the time. the steady rise in communist vote triggered panic among most of the mainstream parties. after trying various solutions to the political crisis, hindenburg again took very bad advice - again from the dnvp. on the basis of this advice, he appointed hitler reichs chancellor on 30 january 1933 who promised to form a coalition with the german nationalists (dnvp). he did so, but at the same time almost immediately unleashed the sa (stormtroopers) who started a reign of terror within two months germany became a dictatorship, complete with concentration camps. joncey

explanation: