SEOUL – Kim Jong Un and North Korea's nukes.

Vladimir Putin and Russian election activities.

Xi Jinping, China tariffs, and new talks on a trade deal.

These issues dominated President Donald Trump's four-day trip to Asia for a G20 summit in Japan and a meeting with Kim at the border of North and South Korea border.

And many of these same issues will linger in the months ahead as Trump seeks re-election, in part by claiming a new kind of foreign policy leadership. He hopes that includes a new trade deal with China and a new nuclear deal with North Korea, each of which he believes will help his domestic situation in the United States.

"The leaders of virtually every country that I met at the G-20 congratulated me on our great economy," Trump tweeted at one point during the week, spotlighting another campaign issue. "We have the best economy anywhere in the world, with GREAT & UNLIMITED potential looking into the future!"

Democrats, meanwhile, will try to cast Trump as an erratic leader who is too friendly with autocrats without getting anything in return. The Asia trip, they said, underscored Trump's weaknesses, including a tariff policy that hurts farmers and consumers.

Democratic strategist Jesse Ferguson noted that Trump also spent a lot of time attacking domestic political opponents during his Asia sojourn, even in the presence of foreign leaders.

"Trump should reimburse American taxpayers for his trip overseas," Ferguson said.

A look at parts of Trump's agenda during his brief trip to Seoul and Osaka, Japan:

China, tariffs, and the American economy

During a meeting on the sidelines of the G-20 in Osaka, Trump and Xi agreed to re-start negotiations on a new trade agreement that had collapsed in May.

As part of that deal, Trump agreed to hold off on new tariffs targeting Chinese products. A new agreement would also void existing tariffs, ending a trade war that Democrats plan to use against Trump at election time.

Thanks to China's retaliatory tariffs,"manufacturers and especially soy farmers are hurting," Democratic presidential candidate Pete Buttigieg said during last week's debate. "Tariffs are taxes."

Trump defends his tariffs, saying they brought the Chinese to the bargaining topic and have encouraged more people to buy more American products. Most economists disagree with him, however.

Some Republicans are concerned that tariffs will hurt their electoral chances in 2020, and feel like Trump needs some kind of new deal with China.

Matt Mackowiak, a Texas-based Republican political consultant, said “we know the tariffs are harming the agricultural industry." But Trump’s base, he said, trusts him on the need to fight what they call China's unfair trade practices.

“It would benefit the Trump re-elect if he can put the trade war behind him, but he needs to achieve a victory for it all to have been worth it,” Mackowiak said,

North Korea and Kim

Four months after Trump's second summit with Kim in Vietnam collapsed, the two met again Sunday in the Demilitarized Zone on the North and South Korea border. Trump became the first American president to actually cross that border and set foot in North Korean territory.

After meeting for nearly an hour, they agreed to appoint "teams" to try and renew talks on a nuclear weapons deal with North Korea, even as the two sides remain at a basic impasse.

The Trump administration says it won't move to lift sanctions on North Korea until it submits specific plans to dismantle nuclear weapons programs; North Korea says it won't provide plans until Trump removes sanctions.

Many analysts question whether Trump will be able to get a North Korea nuclear deal to show voters at election time next year. They said Kim has no plan to give up his nuclear weapons.

"Kim’s intentions all along were to trap Trump into an open-ended negotiation process from which Trump cannot retreat," said Sung-Yoon Lee, professor of Korean Studies with the Fletcher School at Tufts University.

More:Trump arrives at G20 complaining about allies Germany, India and his host, Japan

More:Trump's own brand of diplomacy is on display at G20. How will it fare with Valdimir Putin, Xi Jinping?

Fooling Around With Putin

Trump appeared to joke around when reporters asked him if he intended to warn the Russian leader not to seek to interfere in the 2020 election, as happened during Trump's victorious campaign in 2016.

"Don't meddle in the election, president," Trump said in a less-than-serious manner as he wagged a finger at the Russian president.

Putin just laughed.

Trump also got caught on a hot mike telling Putin he wished he could "get rid" of some people who work in "fake news." This to the leader of Russia, a country where aggressive journalists have been known to wind up dead.

Trump has condemned investigations into Russian election interference, calling them "a witch hunt" by people who are trying to make excuses for their election loss in 2016.

Democrats often condemn Trump's seeming coziness with Putin and will try to exploit that at election time.

After Trump's performance with Putin at the G20, Democratic presidential candidate Kamala Harris tweeted: "It's clear more than ever that the president is a national security threat."

No rush with Iran, China, North Korea

Trump's trip included an unusual verbal tic: frequent claims that he isn't in a "rush" or "hurry" to address some of these pending global challenges.

Tensions with Iran over its nuclear program? "We have a lot of time," Trump said before a bilateral meeting with India Prime Minister Narendra Modi. "There's no rush. They can take their time. There's absolutely no time pressure."

The potential China trade deal? "The quality of the transaction is far more important to me than speed," Trump tweeted Sunday. "I am in no hurry, but things look very good!"

A North Korea nuclear deal? "We're not looking for speed," Trump said. "We're looking to make it right."

Politics At the Summit

Throughout his short trip to Asia, Trump attacked Democratic opponents even while appearing in traditional non-partisan settings.

While attending a series of G20 meetings, Trump tweeted out negative comments about Democrats during their pair of presidential debates. He also ran down the opposition in a pre-meeting photo opportunity with German Chancellor Angela Merkel.

At the final stop of the trip, a speech to troops at Osan Air Base in South Korea, Trump said Democrats "want open borders and to hell with the military."

Trump is planning more foreign trips over the next 16 months pre-election. Don't expect him to quit politicking after he passes the water's edge.

His political rhetoric in Asia did not go unnoticed back home.

"In the old days, no one attacked a President when he's on foreign soil," Ferguson said. "Now, Trump pals around with our enemies on foreign soil and attacks America instead."