Kathleen Wynne subtly drew attention to a difference between her message and what Washington audiences have come to expect during visits from Canada's federal government.
"You may be conditioned to expect a Canadian politician to come to Washington and talk mostly about the Keystone pipeline," Wynne told an audience that included current and former diplomats, lobby groups, and representatives from the U.S. Congress and administration.
"I am not here to do that. That decision is before the United States government and it is not my place, as premier of Ontario, to tell you how to proceed."
A number of people in the chamber were vigorous backers of the stalled pipeline including representatives from the Canadian Embassy, the Alberta diplomatic office in D.C., and industry lobbyists.
A final decision on the Alberta-to-Texas pipeline is expected soon.
Wynne went on to devote much of her speech at the Wilson Center to climate change — praising a U.S. emissions deal with China, and promoting Ontario's intention to join a cap-and-trade system with California and Quebec.
The federal government derides cap-and-trade schemes as a carbon tax. Wynne, however, celebrated them. She called them a proven and economically efficient method, endorsed by the World Bank and the International Monetary Fund.
Wynne also challenged "climate-change deniers" who fixate on the cost of greenhouse-gas reduction efforts, without taking into account the cost of dealing with extreme weather.
She linked climate change to hurricane Sandy shutting down the New York Stock Exchange for the first time since 1888, to the 2013 ice storm that paralyzed Toronto, and to the cold snap that devastated Ontario's apple harvest a few years ago.
"I am fixated on cost too, but I am looking at all the costs," she said.
"That's not a distant or potential threat. That is a changing climate that is destroying the livelihood of people I serve."
She said her granddaughter's generation would forgive today's politicians for getting some things wrong, but would never forgive failure to act on climate change.
The Canadian government, for its part, has just announced greenhouse-gas reduction targets that are slightly higher than the U.S. ones. There are two big caveats, however: they're timed five years farther into the future and, unlike the U.S., Canada doesn't actually have a roadmap for reaching the targets it's already set.
The U.S., meanwhile, has received a fortuitous bounce from an economic trend: a production boom in cheap natural gas, which is phasing out higher-emitting coal in the American energy supply.
After her speech, Wynne had a meeting scheduled with top White House official Valerie Jarrett — often described as the staffer closest to President Barack Obama and his wife.
Wynne praised the work of the Obama administration on greenhouse-gas emissions, including its work with states to set emissions targets for power plants.
The Obama plan is facing lawsuits in the U.S. — but Wynne said the approach would be welcome in Canada.
"I think that it would be helpful if (Canada's) federal government were more engaged both with provinces and territories, and with the American government, on this file," Wynne told The Canadian Press in an interview.
"That's the kind of work we need at the federal level in Canada."
In that interview, she defended the partial sale of Hydro One after provincial oversight agencies banded together to issue a rare group message condemning it.
Eight officers of the provincial legislature, in a public letter last week, bemoaned that the utility would become exempt from things like government audits, disclosure-of-lobbying rules and Access to Information law.
"The fact is that private companies have their own oversight mechanisms," Wynne said.
"There are rules around oversight for publicly traded or private companies. And on top of that we're going to put a Hydro ombudsman in place. We're building in some oversight. So I actually think the oversight will be there."
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