What's the role and meaning of 'pin' in this context?

Question

In yesterday’s central committee meeting of the opposition New Politics Alliance for Democracy (NPAD), party members approved an initiative for nomination reforms, which embattled Chairman Moon Jae-in pinned his position on. With the committee decision, Moon passed a first confidence vote. But another one is supposed to be coming up. The party’s internal schisms are anything but fixed.Ahn Cheol-soo didn’t attend the meeting after his demands for the postponement of the meeting and the withdrawal of a public poll for the confidence vote were not met. The nonmainstream faction of the party walked out in protest of Moon’s decision not to allow a secret ballot vote. That translates into a demonstration of political distrust of Moon.

I'm struggling to understand the role and meaning of 'pin' in the bold line.

I guess the sentence means Chariman Moon can prepare for the battle(obviously the national election), maintaining or keeping his position as a chairman on.

As to my personal syntax analysis,

An initiative embattled Chairman Moon (being) pinned his position on.

S             V           O

'Chairman Moon is pinned his position on '

can be paraphrased as

'His position pins on Chairman Moon.'

I searched the meaning of pin in Merriam dictionary.

1 a : to fasten, join, or secure with a pin b : to hold fast or immobile c : to present (a young woman) with a fraternity pin as a pledge of affection

2 a : fasten b : to assign the blame or responsibility for c : to define or determine clearly or precisely —usually used with down

3 a : to make (a chess opponent's piece) unable to move without exposing the king to check or a valuable piece to capture b of a wrestler : to secure a fall over (an opponent)

It is a transitive verb, so I don't understand how 'pin' works in the sentence in the perspective of both gramar and meaning in context.

Thank you in advance!

Answer 1

Which refers to the initiative for nomination reforms and is the object of the preposition on.

Embattled is not a past-tense finite verb but a past participle employed as an adjective modifying Chairman Moon. It means "confronted or surrounded by hostile forces".

Pin X on Y means "rely on Y for [the success of] X*. Usually we pin our hopes on something; the author has tweaked the idiom a little and seems to be saying that Ch. Moon relied on the initiative to secure that he would continue in his position and power.

Answer 2

To pin means fasten as in Merriam's definition 2 a., as in attach or join.

It is not simple to understand because it is abstract.

Chairman Moon | pinned | his position ... (on/to something)
Subject | verb | object ... (more; such as an "adverbial")

Here is an example. A poor farmer decided that the only way for his family to do well was to educate his only child, a daughter.

The farmer decided to send his daughter to the best university in the land, because she liked to study and did well in school. But the university was expensive. The farmer sold his house, his horse, and his land so that his daughter could finish university and lead the family to a better future.

In this example, we can say that the farmer fastened his hopes to his daughter. He had hope, and he attached all of his hope to his daughter. If she succeeded, his wish would come true. If she didn't succeed, his hope would be lost.

We can say the farmer pinned his hope on his daughter.

In your context, Chairman Moon fastened his position (his job as chairman) to the success of the nomination reforms initiative. If the initiative succeeded, he could keep his position as chairman or be a successful chairman. If the reforms failed, he would lose his position as chairman or be seen as an unsuccessful chairman.

He tied his position to the initiative.