All of these issues and their federal solutions appeal to some group somewhere; that's how many of the issues resulted in new laws. The constitution doesn't support this sort of meddling with individual liberty.
Lets look at these wars on drugs, poverty, fill in the blank. What has been their results. Disaster. Lost freedom, millions in jail. Anytime the government has a war on some problem at home it will result in expanded government power and the loss of freedom. You cannot argue that its okay to expand government power for somethings that you believe, but that its not okay to expand government power for the things that you don’t believe in. The only way to slay the leviathan state is across the board limitations on its power. From a purely economic standpoint, outlawing drugs creates huge incentives for criminals to breach the prohibition. Whether its Al Capone or the Mexican drug cartels, they all spring from the same source, attempted expanded government control over the populace. Remember how well the government’s first War on Alcohol worked out. All subsequent wars have met similar ends.
As far as foreign policy goes, sound money leads to sound policy. If you can’t print the stuff up to finance a war, then the country must agree to the war through higher taxes and legitimate borrowing.
If the US suffers a national economic calamity because such a split weakens the opposition to Obama and the Left's expansion of federal spending and power, I am confident that libertarians will insist that that it is all the fault of GOP social conservatives because they would not accept marijuana and pornography.
In this and much else, the intellectual brilliance of so many libertarians is marred by dogmatism and a lack of political realism. They make me think of oddball, alienated smart kids in high school, proud to be on the outs with everyone but each other. That kind of psychology does not make for winning elections and getting to run the country.
A careful reading of Scalia's rationale in his concurring opinion in Gonzales v. Raich reveals a rationale that limits the reach of the Commerce Clause by requiring it to be coupled with the "necessary and proper clause" in extreme cases. Support and development of this rationale would help to curb the federal commerce clause. In contrast, Thomas's position is untenable even if intellectually bracing.