Conditional "should" instead of "if"

Question

The "should" used in the sentence below is conditional, but I could not figure it out immediately, so I had to reread it several times before I finally understood the meaning of the entire sentence.

The pandemic in Japan will turn into a "man-made" disaster should the travel program go ahead. https://japantoday.com/category/national/Go-To-Travel-campaign-comes-under-fire

I wouldn't have had the understanding problem if the "should" in the sentence had been "if".

My question is when native speakers use "should" instead of "if" to make conditional clause. Is there any specific condition, or is it just a matter of preference?

Answer 1

This usage and placement of should is indeed a shorter way of expressing if (following the example) the travel program went ahead (note the grammatical flexion of to go here).

Both sentences are fine, the example is just slightly more formal in tone and may be emphasizing the condition on the action in question and its consequences more strongly - (this is beyond the scope of your question but) I would read it as recommending against carrying on with the program and emphasizing the (hoped for) unlikeliness of that.

On all other accounts, it would be rather preferential, and the form using should could also happen for unrelated secondary reasons (such as saving space in a very short newspaper article or the like).

The more formal form would be less used in informal speech though, unless you really want to stress the point. In very casual speech, it would be slightly odd to use otherwise.