Is the "to" in the title deletable?

No.

No, the 'to' here indicates the future tense. Without it, it wouldn't be correct, because you would need to say 'abandons' and even then, it changes the meaning of the sentence.

No. This sentence currently means “Trump is going to…” or “Trump is expected to…” or “Trump intends to…” — it hasn’t happened yet. You can also have “Trump abandons…” but this would mean it has already happened.

Not really, and is a very common headlinese also

They already deleted the deletable https://en.wikipedia.org/wiki/Headline#Headlinese Although even "He is to do something" is already shortening I think ("is going to do" or something similar)

No. Not at all. If someone is "to do something" that means they are about to do it in the near future. If you deleted "to" from this title, number one it would creat an ungrammatical sentence (because you need the -s ending in 3rd person singular) and you would have completely changed the meaning in the process. "Trump abandons Russia war crimes prosecution" is a statement in the present tense about something that is a fact already.

Read the headlinese section here https://en.m.wikipedia.org/wiki/Headline Headlines and journalism in general have their own grammar rules essentially.

It's the infinitive for purpose Trump to abandon Trump abandons the pursuit of war criminals Trump abandoning Trump abandon would be subjunctive at a guess, you would need to rework the phrase a bit, Trump insisted he abandon the pursuit or war criminals

Beyond this, deletable would not be the way you'd say that, you'd be better saying removed, or asking " it the "to" in this title necessary".

You wouldn't speak like this in your day-to-day life, but news headlines follow a different set of grammatical rules.

No, this is used to indicate that something is intended or planned to happen in the future. If you take it out, it means it is now happening in the present

1) Strictly speaking, English has exactly two tenses-past and present. Anything else typically requires two verbs. 2) "Headline English" behaves differently than "regular English". This headline isn't in past tense and it isn't in present tense. Therefore, we will probably need two verbs. In "regular English", a writer might say something like "Trump *will abandon* prosecution of Russian war crimes." In grammar school, this is called "future tense", even if we had to use two verbs to say it. (A strict grammar teacher would say that anything that needs two verbs to say[ is a mood or an aspect](https://en.wikipedia.org/wiki/Tense%E2%80%93aspect%E2%80%93mood), not a "tense".) "Headline English" is a special type of English that was created for newspapers. Headlines typically have large letters to make them easy to find on the page. The pages themselves have limited space. Therefore, newspaper writers came up with many shortcuts. One of those is replacing "will <verb>" with the slightly shorter "to <verb>".

No, you can't edit post titles. 😅

No…’to’ is being used here to indicate the act will happen in the future. Without it would make no sense.

Yes, but it would include changing the meaning. You could delete it and add an s to the end of abandon, making it "abandons". This means he already has done it. Or you could just add a comma after "Trump" and delete it. This would make it a request

No. It could be re-written to "Trump will abandon Russia war crimes prosecution". "Trump abandon Russia war crime prosection" would be in the wrong time (present instead of future) and it would also be incorrect because the "abandon" would need to be changed to "abandons"

To : he is about TO… / he is going TO…

This is typical of news headlines; I personally consider it to be a shortening of "X is going to..."

No

No, this is an infinitive future construction in a "headlinese" short form (short for "is going to").

trump is to abandon or was to is it ok ?

Headlines often use the to-infinitive form to refer to future events https://dictionary.cambridge.org/grammar/british-grammar/newspaper-headlines

No but it is replaceable. Example: Trump Will, Trump is going to, Trump plans to

No. If you removed "to" it would have to be replaced with "will" (which I would say slightly changes the meaning/implication) OR the tense would have to be changed (remove "to" & add make it "abandons") but that definitely changes the meaning.

No. It implies (something like) “Trump is about to abandon..”. / “Trump is going to abandon…” You could write Trump abandons…, but that’s changing the meaning to present tense instead of future.

No. It implies that it will happen in the future.