PALM SPRINGS, CALIF. — In the temperate desert outside of Los Angeles, Charles and David Koch have orchestrated the largest gathering of their Seminar Network yet held, hosting around 550 men and women who have donated at least $100,000 to the network’s libertarian initiatives. And after scaling back early projections on their spending during the 2015-2016 cycle, they intend to ramp up spending on work to build grassroots networks and impact U.S. policy. That spending is expected to rise from the $250 million ’15-’16, to an estimated $300-400 million in 2017-2018.

“Usually we’re talking about stopping the worst things coming out of D.C.,” network Co-Chairman Mark Holden told reporters. “We see an opportunity to play some offense and get some things done.”

Held twice a year, this weekend’s seminar will be the first since the election and inauguration of President Donald Trump. The network spent hundreds of millions on advertising and advocacy for limited-government politicians — namely, Republicans — running for the U.S. Senate and the House of Representatives, but notably stayed out of the presidential primaries and race. The network is co-chaired by Charles Koch Institute President Brian Hooks and Holden, who is also general counsel for Koch Industries.

“It’s been defense for our side, mostly, trying to stop bad things from happening… or at least mitigate the bad things coming out of Washington.” Americans for Prosperity President Tim Phillips told reporters.

Citing the Trump administration’s moves to cut regulation and re-establish the Keystone Pipeline, seminar leaders sounded optimistic, but as for the GOP’s proposed “border adjustment tax,” it “is a no-go for us,” Seminar Network spokesman James Davis said. (RELATED: Three Republican Senators Kick Off Koch’s First Massive Donor Conference In Age Of Trump)

When leadership remarks opened up for questions, reporters were quick to ask about the network’s relationship with the new administration, citing the lack of support given Trump’s candidacy.

It was “a presidential election year where we couldn’t get comfortable with either candidate and didn’t think we could be impactful,” Holden said, but, “We’ve had a number of good friends of ours who worked in the network who are in the White House now… We had discussions with their team during the campaign, we talked policy with them, they were civil meetings.”

Indeed, the new administration is more colored by their lieutenants than any in American history. Vice President Mike Pence enjoyed network support as Indiana governor, and one of his former top advisers and the Koch’s top operatives, Marc Short, is now the legislative director for the White House. Short has used his knowledge of the Koch’s key personnel to help staff the executive. In contrast, in the most famous conservative administration, President Ronald Reagan’s, the Kochs were on the outside. David Koch ran against Reagan on the Libertarian ticket in 1980.

“Some of the appointments are encouraging as well,” Phillips said, citing Rep. Tom Price’s nomination to lead the Department of Health and Human Services, which oversees Obamacare, and Oklahoma Attorney General Scot Pruitt’s nomination to head the EPA. Since President Bill Clinton’s administration, Charles and David Koch have battled Washington on both government-provided health care and what they call over-burdensome environmental policies.

In the past year, the Seminar Network has found itself in opposition to one major player in the administration, attorney general nominee Sen. Jeff Sessions, on criminal-justice reform at the federal level. “We’re doubling down on [criminal-justice reform] as well,” Holden said, adding that he is happy with progress made in states, but would be putting a renewed focus on D.C. Citing the incoming attorney general’s past work on federal drug reform, he said he’s optimistic about working with Sessions’ Department of Justice. “What happened last year, I think, was election-year politics.”

Called “A Time to Lead,” the meeting is hosted at the Renaissance Indian Wells Resort and Spa, and is focused on local, grassroots initiatives Americans can take in what Hooks called “the key institutions of society”– “education, community, business and government.”

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Editor’s Note: Christopher Bedford was a fellow at the Charles Koch Institute in 2010.