Tokyo's previous warnings not to trust Pyongyang have been dropped as both Washington and Seoul barreled forward with engagement. Abe is now seeking a summit with Kim for himself, rather than be further left out of North Asia's rapidly changing political situation.
While Abe had cultivated close ties with Trump, becoming the first foreign leader to meet him after his election, he has also faced disputes with the US leader over trade.
"It's a sign of the continuing close relationship that he was granted a meeting at short notice," said Euan Graham, director of the International Security Program at Australia's Lowy Institute.
"But the shine is coming off there, too, given Trump's tendency to apply leverage freely between economic and security issues."
Protests and polling
Tens of thousands protested outside Japan's Parliament in Tokyo on Saturday, calling Abe a liar and demanding his resignation over a corruption scandal which has dogged his premiership for months.
While this weekend's protests did not come near the size of rallies in 2015 protesting Abe's push to expand the military, the combination of pressure from within the LDP and from the public has some questioning whether Abe can hold on.
"Abe appears unable to shake off the scandals," said Graham, though he pointed out "there was a time when serving Japanese Prime Ministers would be lucky to register more than 20% popularity ratings."
"But it is the stickiest period he has faced since returning to the premiership, without question," he said.
Trade deal
Duncan Innes-Ker, Asia regional director at the Economist Intelligence Unit, said there was "no question" that Abe had been hurt by the ongoing scandal.
"Against this background Abe badly needs a win," he said.
The Japanese leader may be hoping that win will come at Mar-a-Lago, where, according to a statement from the White House, Trump and Abe will "explore ways to expand fair and reciprocal trade and investment ties between the United States and Japan."
Innes-Ker said Trump "could potentially offer concessions on the steel and aluminum issue or he could signal a US intention to rejoin the (Trans-Pacific Partnership)."
While "both would be seen as a triumph for Abe," he warned they would not come without concessions from Tokyo.
While Trump did surprise observers by indicating last week he may be open to rejoining the TPP -- an Obama-negotiated trade deal he once slammed -- the White House is more likely to push Tokyo to sign a bilateral deal less to Abe's liking.
Security concerns
Since returning to the premiership in 2012, Abe has made security a key plank of his appeal. His tough response to North Korean missile testing last year was a key part of his election campaign during last year's snap election.
Abe's hawkish posture seems to have backfired, however, with both Seoul and Washington pursuing engagement with Pyongyang.
"On North Korea, Japan now looks the most isolated of the allies. It has even tried reopening independent contacts with Pyongyang, and is conducting fence-mending diplomacy with China currently," Graham said.
"But Abe has made his choice to double down on the US Alliance, and cannot be expected to reverse course now."
One major concern in Tokyo is that a US future deal with North Korea could result in Pyongyang retaining missiles which can target Japan.
He said he would call on Trump to push North Korea to "also abandon short and intermediate-range missiles that put Japan within range."
"Even South Korea is struggling to get its voice heard as the denuclearization push increasingly becomes a US-China-North Korean discussion," Innes-Ker said.
"It is not clear that any party is sidelining Japan as a conscious move, but they are certainly not reaching out to include it, and its priorities could get pushed down the list as a result."