Should retroactive divorce (a la David & Batsheva) be reinstituted?

Question

Almost all the commentaries on David and Batsheva's seeming indiscretion follow Rashi who points out during that time a retroactive divorce was given upon the husband leaving for war, therefore ensuring that if the husband nor his body return from war the widow will not be an aguna and will therefore be able to remarry. The nature of a retroactive divorce ensures that if the husband does return from war no divorce took place. (This is contrary to Rabbanu Tam who says that an outright divorce with a promise to remarry was given).

Should we all be giving/receiving these retroactive divorces today given the terrorist threat and the unfortunate situation of terror making it possible that our loved one may not return home to us?

Answer 1

I think Isaac's nailed it, in a comment on the question:

The average person's chances of chas veshalom getting killed in a terror attack today are, thank God, nowhere near the same league as those of someone who goes out to war.

Two more points to consider:

• In the decade 2000-2010, there were b"H fewer than 1000 deaths by terrorism in Israel, a country with some 7 million people during that decade. That's fewer than 14 deaths per million per year. Of the more than 300 million people in the US, some 43000 die annually in traffic accidents. That's more than 140 deaths per million per year, ten times as many as by terror in Israel. By the logic in the question, everyone (except perhaps kohanim) should divorce his wife in the States, too, not just Israel. (That's not really an answer to the question, just a comment. I'm just sticking it in here since I'm answering already.)
• I think the process of writing and giving a divorce — not the simplest of matters — every single day (in case chas v'shalom the person doesn't return that day) is infeasible.

Answer 2

The question has been raised in contemporary times vis-a-vis Israeli soldiers. (And if I recall correctly from a lecture by Rabbi J D Bleich, Jewish soldiers in the British Army during WWII as well.) As Rabbi Bleich pointed out, in today's information era there are exceedingly few cases of people who outright disappear at war. (To prove his point, he asked "how many US Vietnam MIAs are there today?") An additional wrinkle is that the Get would say "if I don't return within time X"; often with today's wars it's not uncommon for soldiers to return home every so often, not quite knowing when they'll be deployed; so a soldier would have to do a new retroactive Get each time he leaves.

The retroactive divorce was also proposed as a solution to the other agunah problem ("Type II Agunah", as Rabbi Breitowitz puts it; or as Rabbi Rakeffet says, "man-made agunah"), that of the husband who is clearly alive and right here, but refuses to give a Get. Why not, the day after the wedding, have the husband hand his wife a paper that says "you are hereby divorced from me right now if at any point we spend 2 years not living under the same roof." The objection to this came in the early 1900s from (if I recall correctly) Rabbi Isser Zalman Meltzer, who raised the following possibility of an unintended consequence:

In our current system, there are plenty of guys out there who are going through rough times in their marriage, but will stick it out and try to improve things. (Or if G-d forbid things really are serious and irreparable, go through the right process to make clear it's over and how to settle it.) They know that leaving a woman an agunah is utterly reprehensible. But if we have everyone giving their wives this conditional divorce now, what's to stop a husband from running off to who-knows-where and abandoning his wife? He knows that in 2 years no matter what, she'll be free to remarry!