Upvote:2
Yes weaker powers rarely attack their much stronger neighbors.
A wise general never starts a war he can't win.
But if there are many small states then they will fight each other a lot, think medieval Europe.
There are a few cases where weak powers attack stronger foes.
One is a rising or falling power A weak power is growing quickly in strength think Germany after it unification by Bismarck. It wants to gain resources and worries that it will soon be attacked by the current great powers to keep it from growing to much, and being a threat. Since it thinks it will be attacked it attacks first to gain tactical surprise in the "inevitable" upcoming war. But even with surprise Germany was unable to overcome its stronger neighbors Russia France England and the US, in WWI, though they did beat Russia. Also a weakening state might fear it would soon be attacked so it might choose to fight now when it has slightly better odds
The other is crazy leadership Think Kim Jong ill North Korea routinely threatens war against their military more powerful Sothern neighbor, and antagonizes the military powerhouse that is China. Foolish generals might do anything.
Also yes bigger nations can field bigger armies for bigger and bloodier battles, even if they work harder to prevent war and casualties then their smaller neighbors.
Upvote:2
No, there is at best a weak correlation between national size and tendency for belligerence. Some examples of "small" states that started significant wars:
Recent declaration of statehood by I.S.I.L.
North Vietnam attacking the U.S. ally South Vietnam
Italy (very definitely the junior partner of Germany and Italy) invading Greece in 1940.
Nazi Germany invading U.S.S.R. in 1941
Prussia under Frederick invading Silesia to start War of Austrian Succession
United Provinces rebelling against Spain (1588, beginning of Eighty-Years War)
Sweden under Gustav Adolphus invading Germany in 1630
Macedonia under Philip V declaring war on the Roman Republic (215 B.C. - First Macedonian War)
Macedonia Under Alexander invading the Persian Empire