Yes the government can sell treasury bonds which is why we’re so in debt.
The Korean War was the first battle of the Cold War, and first major proxy war fought between the United States and a Soviet communist supported enemy. A proxy war occurs when one or more opposing powers instigates a war and then uses third parties to fight on their behalf.
The Best Explanation for why the Cold War is not Included in the chart Is because:
~That was not a Conventional War, and its Costs are Measured by the Individual Proxy Wars.
Hope this helps.