He didn’t wear his famous jean jacket for his first speech on the Senate floor, but David Perdue still talks about Washington as if he’s an outsider, not an insider.

“I’m trying to help people have a greater sense of urgency on what I think are the greatest crises of the day,” Perdue, Georgia’s brand-new Republican senator, told me by phone recently.

If describing the debt and deficits as a crisis sounds so 2010, keep in mind that Perdue last year elbowed his way past an experienced GOP primary field by talking about the threat they still pose — and the inability of longtime Washington insiders to rein them in.

“We had about six weeks to deal with six years of irresponsibility, and we came up with a budget, and it’s the first budget we’ve had in a while, and it’s the first one that balances (over time), I think, since 2001,” said Perdue. “But it’s not a panacea, it’s not where it needs to be.”

Not, he said, with the debt where it is. “We’ve passed the tipping point with regard to this debt, big-time,” he said. “We have $18 trillion in debt. If interest rates today were at their 30-year (average) rate of just over 5.5 percent, we’d already be paying over $1 trillion (annually) in interest. That’s just not manageable.”

That’s not to mention unfunded future liabilities for Social Security and Medicare: “Those are things that we’ve got to deal with today. … We’ve made commitments we can’t afford.”

Regarding commitments, Perdue spoke at length about two treaties pursued by President Barack Obama: a nuclear deal with Iran and a trans-Pacific trade pact with 11 other countries.

On the Iran deal, Republicans were deeply skeptical while Democrats wanted to give Obama wide latitude. On trade, it was the other way around. In both cases, the solution seems to be allowing the president to go forward, but retaining congressional ability to pull the plug.

“I think anything that would allow Iran to eventually get a nuclear weapon … something like that, I don’t think would be acceptable here,” he said. “Not now, not in 10 years, and really not ever.

“You had an argument at one time that you only had two choices: negotiate this deal that Iran wants, or you go to war. There’s a third option, that if they don’t agree (to a good deal), you double down on sanctions.”

On trade, Perdue said a deal could increase our exports to major markets like Japan and Australia: “Savannah right now is the only port in the country that exports more than it imports.”

“What’s at stake here, I believe, we’re trying to develop this Pacific partnership with 11 other countries,” he explained. China, meanwhile, has a parallel effort with some of those countries and others.

“If we fail … China very likely will create a replacement for that with 16 countries, and therefore we won’t get most-favored nation (trading) status with those countries,” hurting our economy.

Even with that prospect, some Democratic senators have threatened to block Obama’s ability to negotiate the trade deal. “This is an example, if you think about it, of the gridlock up here,” Perdue said. “And how partisan politics get in the way of doing the right thing.”