And the senator, himself, acknowledges that his push for major climate change legislation is going nowhere for now. He calls his public pronouncements on the issue an attempt to keep up morale on the left and "bring the day, earlier, when things change — and suddenly what was impossible is now possible."
Whitehouse's partisan broadsides, then, which can seem so loud and immediate — so of the moment — are really a long-term play, a slog. Heroic in the eyes of his liberal supporters, perhaps, but of indeterminate value.
And if the Republicans do eventually come around, says analyst Jennifer Duffy of the Washington-based Cook Political Report, Whitehouse will face a crucial question: having staked out such strong positions on these core issues, is he willing to compromise?
There is reason to believe he is. Rhode Island's junior senator, for all his party-line advocacy, has found opportunities to work with Republicans on a few issues: cybersecurity, for instance, and a push to protect the oceans.
And when I asked him if he'd be willing to compromise on what may be the most important issue on his plate — climate change — he said "yes." But you've got to have your sticking points, he added.
Carbon pollution has a real price, he said, and we've got to require payment. We've got to impose a carbon tax. That's non-negotiable.
It's hard to see the GOP accepting that as a starting point any time soon.
David Scharfenberg can be reached firstname.lastname@example.org. Follow him on Twitter @d_scharfenberg.