Both are excuses to justify expanding the size of government. Because of that, neither will ever go away (unless, of course, we sometime reach the point in history where freedom and liberty come to mean more than the acqusition of wealth and power, to the plutocrats, and largess to the People).
Conservatives are as eager for a nebulous and never-ending "war on terror" as they are for the WOD. As long as "there's a war on!" there's an excuse to tell dissenters that it's "unpatriotic" to criticize Bush. (NOT!)
The best way to fight drug use is education and health care (i.e., the same way we fight alcoholism). The best way to fight terror is foreign non-intervention. (There's a reason the Swiss have little problem with terrorism.)