Mach 6 SR-72

Against who?

We already have thermonuclear weapons and are busy reducing our stockpile of chemical weapons. Seems we have enough killing power without this. Using this against another nuclear capable country probably has a sad ending (and all sides know that). So another super advanced ultra-expensive technology vehicle...to take the fight to Afghanistan, Iraq, Iran, Syria, North Korea?

 

Doesn't matter. Those who fund, approve and design first-strike weaponry don't think like normal rational people. The drive to get "there" faster with better weapons has never stopped.

 

I cannot disagree there. But I would point out those who fund, approve, and design are three very different groups (taxpayers, Legislators, Military Contractors) with very different agendas.