It looks obvious

We have several times invited the former vice president to present his famous slide show at the Cato Institute, in conjunction with a slide show prepared by Patrick J. Michaels, who takes a more benign view of climate change.

[...]

Gore’s office has declined our invitations. If Vice President Gore is committed to public understanding of climate change, why will he not demonstrate to a Washington audience composed of both supporters and skeptics that his ideas can carry the day in a dialogue with a leading critic? He wiped the floor with Ross Perot; does he fear that the case for catastrophic climate change is not as strong as the case for NAFTA?

The invitation is still open. Mr. Vice President, please come to the Cato Institute and present your slide show to an audience of journalists and scholars with a knowledgeable climate scientist also on the dais.