your link is not to the constitution or even a discussion of the constitution, its a policy wonk yapping about what he thinks the constitution allows. he is wrong.
the constitution allows for the president, and the congress to:
negotiate trade with foreign powers
negotiate treaties and territory with foreign powers
tax foreign imports and us exports to foreign lands
defend the nation and it's constituent states against enemies, both foreign and domestic
regulate (make regular, not control) trade between states within the union
ensure fair dealings between states and between individuals across state lines
nowhere does the constitution institute a power to police foreign lands, send US citizens to foreign lands as hessians for a foreign power, or loan out us citizens as cheap construction labour in far off lands.
LESS involvement with foreign affairs, not more is what we need, and the constitution demands.
when you cut through all the bullshit and double talk this is what your linked article gives us:
US soldiers fighting to defend a french colonial province's authoritarian imperial regime from the people who live there (vietnam)
US soldiers fighting for the stabilization of an indefensible border separating 2 sides of a civil war, and keeping these two sides from fighting at our expense for 60 years (korea)
US soldiers fighting against ALL SIDES in an internal power struggle that no side can win (somalia)
US soldiers fighting and dying to on behalf of an invading force hostile to the US, and aiding it's attempt to annex the land of a friendly foreign power (kosovo)
US soldiers trying to execute a failed program and policy designed to force people to adopt western values and society, when they just dont want it. (iraq, afghanistan, libya and coming soon, iran and syria)
WW1 and WW2 were mutual defense treaty operations, and fall within the scope of constitutionally granted congressional and presidential authority.