What aspects of romanesque architecture caused early scholars to call it roman-like?

Romanesque architecture is obsessed in semi-circular arches, massive walls, barrel wall roofs (barrel vault) and decorative arcades (succession or arches on a walkway). It is markedly different from Gothic architecture, which is characterized by use of pointed arches. If you are thinking about fairy-tale castles and stuff, you are probably looking at some elements of that architecture. Romanesque architecture flourished approximately 6th to 11th centuries, and it is widely adopted by castles, monasteries, and churches. It got its name probably because of the arches, which is a feature typical in Ancient Roman architecture. Actually, the word Romanesque was coined in the 18th century. 

no because we were not ready for war

after the roman empire, the catholic church began to unify by taking on many duties of a government.