(CNN) Aside from his "Rocket Man" rhetoric, President Donald Trump's United Nations debut revealed a new road map outlining his plans to deal with one boiling nuclear crisis, with North Korea, and another one that may reignite, with Iran.

None of the tactical adjustments made during four days of intensive diplomacy in New York are likely to immediately thwart North Korea's race to tip a long-range missile with a nuclear weapon, or ease suspicions about Trump's hostility to an Iranian nuclear deal that appears to be working.

But the President's diplomacy at the UN did suggest that the administration is moving beyond rhetoric and posturing on both crises to enact action plans, however, controversial or tentative they may be.

Administration officials appeared this week to connect the two issues, which dominated Trump's talks over the course of his four-day visit.

"We don't want to be dealing with the next North Korea," Trump's ambassador to the UN Nikki Haley said on Thursday while discussing the prospects of the Iran deal.

North Korea

The President's priority heading to New York was to light a fire under international efforts to further isolate and punish North Korea, following a volley of missile tests and its most powerful nuclear blast.

Step one was his stunning warning that it might be necessary to "totally destroy" the isolated state in defense of America's security and allies, a threat that shocked the world and was chilling coming from the lips of a US President.

On Thursday, he reverted to more traditional statecraft, giving the Treasury new authority to impose sanctions against firms that trade with North Korea, in a move that potentially opens the way for the US to take aim at Chinese businesses that bolster Kim Jong Un's regime.

He also praised Chinese President Xi Jinping for what he said was a "bold" and "somewhat unexpected" order by the central bank in Beijing for its banks to fully implement UN sanctions against North Korea.

Both developments are highly conditional. It is not yet clear if the US is yet ready to actually impose widespread sanctions against Chinese entities that deal with North Korea, a move that could trigger a significant political backlash in Beijing.

It's also all but certain that Friday's developments will not change Kim's blanket refusal to give up his nuclear program, or will shift China's calculus, which has always stopped short of imposing decisive pressure on Kim.

But after months of pressing Beijing to do more to rein in its recalcitrant neighbor, Trump could at least claim the central bank's initiative as a preliminary foreign policy victory.

"That was a tremendous move, and we have great respect. And we also would like to thank President Xi of China. So that was a great thing he did today," Trump said, as he met Japanese Prime Minister Shinzo Abe.

Bruce Klingner, a former CIA Deputy Division chief for Korea told CNN that the new sanctions "do seem to be significant" and were the result of leverage brought to bear on the Chinese government by the White House.

"My sense would be that Beijing's announcement today that all of their banks would stop dealing with North Korea was really a way to avoid the US imposing sanctions or imposing fines on Chinese banks," Klingner said.

"It's a very big step because I think we should be cynical and skeptical," he said, noting that in previous years Chinese enforcement had been "timid and sporadic."

Emphasizing the intricacy of diplomacy with the Chinese, Treasury Secretary Steven Mnuchin stressed that the sanctions were "in no way specifically directed at China."

Political sensitivities between the Trump administration and China are particularly acute ahead of the forthcoming Congress of the Chinese Communist Party and the President's expected visit to Beijing in November.

Iran

While Trump strives to defuse the North Korea nuclear crisis, he risks reopening a showdown with Iran, after hinting he is ready to ditch the nuclear deal agreed with the Islamic Republic agreed by the Obama administration.

He blasted the agreement as an "embarrassment to the United States" during his UN General Assembly Address but encountered opposition to the idea of abrogating it from US allies including Britain and France.

Even Secretary of State Rex Tillerson admitted that Iran was honoring the pact, less than a month before Trump must certify whether it is compliance.

The White House, however, says that Iran's ballistic missile tests and what it sees as threatening behavior in the Middle East infringe the spirit of the deal, even though such issues were excluded from the original agreement.

In New York, it became clear that Trump is mulling a gambit that stops short of killing the deal but seeks to drive Tehran back to the negotiating table.

The President hopes to address the "sunset provision" that allows some curbs on Iran's nuclear program to expire after 2025, and to address Iran's ballistic missile program, administration officials said.

He won some encouragement when French President Emmanuel Macron used an interview with CNN's Christiane Amanpour to warn Trump against buckling the deal but also expressed an openness to consider adding new provisions.

Still, even this approach is fraught with uncertainty.

While European nations might be interested supplementing the deal, they oppose any steps that jeopardize the current arrangements.

"The Americans are right: Iran is still not playing a constructive role in the Middle East, be it in Yemen or Lebanon," said German Foreign Minister Sigmar Gabriel in a statement.

"We agree that we must discuss and address this, but not by means of a working regional nuclear arms control agreement."

European allies might join Macron's attempt to provide political cover for Trump to certify the nuclear deal over his own objection. But Trump may hit a familiar roadblock -- Russia and China.

As with the North Korea crisis, neither nation has a clear national interest in helping the United States solve foreign policy nightmares that call into question its credibility and power.

There's also a practical impediment to Trump's approach. The centerpiece of the deal involved lifting international sanctions that were pulverizing the Iranian economy in return for a freeze on Tehran's nuclear program.

Without the sanctions, much of the world's leverage on the Islamic Republic is gone -- as Iranian President Hassan Rouhani well understands.

"There will be no return, no renegotiation and no changes," Rouhani told reporters in New York.