Sen. Rand Paul (R-Ky.) criticized other legislators for ducking a confrontation with President Obama over Libya on Wednesday, saying Congress had become “not even a rubber stamp, but an irrelevancy” in matters of war.

Paul made the comments in a speech Wednesday morning at the District campus of Johns Hopkins University’s School of Advanced International Studies. The freshman senator, a favorite of tea party groups, said he would try to derail a proposed resolution of support for the Libya military mission.

“We will try to amend whatever Libya resolution comes out,” Paul said, by adding language decrying the use of force without congressional permission. “We will try to strike theirs, and replace it with ours.”

The military campaign in Libya, now more than two months old, has been the target of rising anger on Capitol Hill. Many legislators — including conservative Republicans — have raised questions about the War Powers Resolution, a 1973 law that requires presidents to obtain congressional authorization for foreign campaigns.

Last month, the 60-day deadline for that authorization came and went. Last week, the GOP-led House passed a resolution rebuking Obama and demanding that he make the case for the campaign within two weeks.

In the Senate on Tuesday, a resolution supporting the campaign appeared to stall, while other legislators worked on an alternative that could mirror the bill the House passed.

Paul’s speech — intended to lay out a “conservative constitutional” model for foreign policy — used the Libya campaign as a demonstration of the problems with the current model. He said even many fellow conservatives seemed willing to cede warmaking powers to Obama, despite the War Powers Resolution.

“The real hypocrisy of the conservative movement is that they claim to be such fans of the rule of law,” Paul said. “But they sure aren’t willing to follow it, when it comes to how we go to war.”

Paul laid out a broader foreign-policy platform that he called “moderate,” saying he was uninterested in using the U.S. military to help build up other countries. In particular, he said, the process of nation-building was hard to justify in countries that were “nations in name only,” based on boundaries drawn from outside.

He seemed to be talking about places like Libya, Iraq and Afghanistan — all split by rivalries among ethnic groups or tribes.

“Instead of large, limitless land wars in multiple theaters, we would target our enemy, strike with lethal force and leave,” Paul said. “We would not presume that we build nations, nor would we presume that we have the resources to build nations.”

The plan contained few specifics, however. Paul said that his position was to have U.S. intervention “somewhere, some of the time,” but gave little detail about how those chances should be chosen.

For now, Paul said he felt “lonely” holding these positions, but said that mounting national debt would bring others around.

“An expansive foreign policy will end,” he said. “Because we’re out of money.”