Kaine deserves special credit on this issue because he was willing to stand against an administration of his own party. Too often, politicians only invoke constitutional limits on executive power when the other party holds the White House. Kaine’s stance is a particularly impressive contrast with Donald Trump, who has zero respect for any constitutional constraints that might be inconvenient for him.
From a libertarian point of view, Kaine also has a good record on immigration and free trade, an issue on which both parties have gotten worse in recent years. He once even described his support for free trade agreements as “passionate.”
On most other issues, Kaine is a generic liberal Democrat, which I am no fan of. I am even less a fan of Hillary Clinton, who is both more left-wing and far less principled on constitutional issues than Kaine. Still, the Kaine pick is a step in the right direction on her part, and is about as good as we could realistically expect. It is an obvious effort to reach out to moderates, conservatives, and libertarians who cannot stomach Trump, but (for good reason) remain wary of Hillary.
Kaine notwithstanding, Libertarian Party candidate Gary Johnson is far preferable to either Trump or Hillary Clinton. He’s currently gaining ground in the polls. But it is still very possible that Johnson will turn out to have no realistic chance of winning. In that event, the Kaine pick further strengthens the case for concluding that Hillary Clinton is a much lesser evil than Trump. If the election ends up being a binary choice between Clinton and Trump, people who care about limiting government power now have even more reason to choose the one that is wrong within normal parameters, as opposed to the European-style neo-fascist.
And, finally, here is his June 2014 Washington Post op ed on the subject:
Last week, both the Obama administration and certain members of Congress said that no congressional authorization is needed for U.S. military action in Iraq. I deeply disagree.The framers of the Constitution gave Congress the power to authorize war. As James Madison wrote, “The constitution supposes, what the History of all Governments demonstrates, that the Executive is the branch of power most interested in war, and most prone to it. It has accordingly with studied care vested the question of war to the Legislature….”Ultimately, the allocation of war powers is based on a value. The nation should not send U.S. service members into harm’s way unless there is a consensus among the civilian leadership — executive and legislative — that the mission is worth it. Ordering people to risk their lives without Washington doing the work necessary to reach a political consensus is immoral.