Dear April:
As
danielpalos had pointed out where Liberals are getting this from the Constitution, the first enumerated power of 18 lists the two most cited roles of govt: Common Defence (which Conservatives/Republicans focus on) and Tax and Spend/for the general welfare (which Liberals/Democrats focus on).
L/D write their platform policies to focus on internal/social/domestic issues.
They run the govt and their campaigns to focus there. That is what they do.
Like mothers of the household focusing on family and social matters.
C/R focus on law enforcement, national security, interstate commerce and foreign relations, and economy. Mostly External issues while leaving social and personal matters to the people.
That's why D are ill suited for defense that requires a strong deterrent authoritative approach. That is what R are for, where Conservative leaders are not going to focus on social uses of govt but on security and defense.
Until we set up dual administrations that allow both Internal and External leaders over respective policies, we will see failures on both left and right, by trying to play both roles instead of delegating respectively and sharing these duties.
So when leaders and parties fail in one area while succeeding in another, both left and right will complain about the other.
Instead of competing, we should elect both internal and external administrations, and only elect and assign parties to what they specialize in that taxpayers approve.
By delegating duties accordingly, we won't have these problems.