Once again you break out that idiotic meaningless axiom. The Constitution gives Congress blanket authority to make war.
No there isn't. The Congress can only operate within the limits of their express powers listed after Article 1, Section 8, Clause 1.
Completely irrelevant statistic. The U.S. pays its soldiers far more than other nations and spends more on their welfare and well being both while they are in the military and afterwards than any other nation. Also please read the following: https://www.bloomberg.com/opinion/a...pends-the-u-s-on-the-military-here-s-the-math
That clause is stating the purpose for the powers listed in the clauses that follow it. The Founders had no problem with the concept of "common offense" when they fought Native American tribes or the Barbary Pirates.
The concept of "welfare" meaning "social programs to solve poverty" didn't even exist when the Constitution was written.
"General Welfare" in the context of the Constitution means "Overall Welfare". Not that the government would solve every individual's problems for them.