after it has been done/ after the event/ ex post facto
After the deed. Once the thing has been done (literally from Aramaic, 'd'i avad', meaning 'if done, once done').
("After the fact, but not initially, this teaches us" – Sukkah 9b, and also: "The Sinai Campaign was not intended to be a preemptive war... However, after the event, it became a deterrent to Arab ambitions to strike at it" – Moshe Dayan / Sinai Campaign Diary)
Translation
Expression (Hebrew)
בְּדִיעֲבַד
Definition (Hebrew)
לְאַחַר מַעֲשֶׂה.מִשֶּׁנַּעֲשָׂה הַדָּבָר (מִלּוּלִית מֵאֲרַמִּית: לִכְשֶׁעָשָׂה, מִשֶּׁעָשָׂה).
("בְּדִיעֲבַד, אֲבָל לְכַתְּחִלָּה לֹא, קָא מַשְׁמַע לָן"- סוכה ט ע"ב, וְכֵן:"מַעֲרֶכֶת סִינַי לֹא נוֹעֲדָה לִהְיוֹת מִלְחֶמֶת מְנַע...אוּלָם בְּדִיעֲבַד הָיְתָה לְגוֹרֵם מַרְתִּיעַ לְשְׁאִפוֹת הָעֲרָבִים לִפְגוֹעַ בָּהּ"- מֹשֶׁה דַיָּן/ יוֹמַן מַעֲרֶכֶת סִינַי)