My own personal feeling is that prophecy is a subject that is best left alone, or at least, left in the hands of those professional theologians who are willing to stick their necks out, on the line by interpreting prophecy. The lessons learned from the WT experience of Bible prophesying should have taught us that this is a hazadous occupation, at best.
I feel that if there is a prophecy mentioned in the OT, which has clearly been fulfilled, then there simply is no need to trace any further meaning in that prophecy. This applies to such a prophecy as that mentioned in Dan 4, regarding the "seven times" Since the Bible itself has said that all the prophecy was fulfilled in king Nebuchadnezzar, to then give it a further meaning, as the WTS does, making it pertinent to our times, no less, is patently absurd. In my opinion, of course.
In prophecies such as those that may have more than one meaning, the first having been fulfilled in the past, then the second meaning must rest on Scripture alone. As Doug mentioned earlier, if no NT writer has indicated a fulfillment in a certain time frame, then to make that second application fit into a theologically moulded framework, supporting a preconceived teaching, is false and smacks of cultism. This may apply to such a prophecy as Matt 24. If it does have a fulfillment beyond the timespan of Christ's words, then that second application must have a Bible approved interpretation. If the last Bible writer, the apostle John said nothing about when that second application was to be, then we can confidently be assured that the Bible canon has left that second application in the future, awaiting an authoratative interpretation by the Lord Himself at His Second Presence which is still in the future. There are those who regard all of Matt 24 having been fulfilled. Thats fine and part of legitimate Bible interpretation. There are others who feel that there is another fulfillment in the future. Well, thats fine as well, whether one agrees with that or not, because that too, is legitimate Bible study.
The exception comes when one applies that second application to our own present time, casting around for modren anecdotes to fit into this preconceived mould. As the examples of such as Herbert W Armstrong, or the WTS, who see themselves in that setting, have taught us, this is dangerous and ultimately futile. It is cultic in thinking. It also requires credulity, and not faith to accept.
The same is with the prophecy at hand, Isa 2. Oddly enough, I don't see any "first" fulfillment in either Isa himself, or in later Israelite history. It must therefore have a fulfillment futute to Isa. When? Dunno.
Reformed theology sees the "last days" as stretching down from the day of Pentecost, since many NT writers understood their times as in some way the "last days" - Isa 2 may therefore belong to Church history, or at least the 1C AD for its fulfillment.
Dispensational theology sees the last days as still in the future, involving the Millennium. If this is so, [I am a dispensationalist myself] then Isa 2 must have a millennial fulfillment with some form of future Israelite assendancy being outlined. If again, this is so, then the details await further, authorative clarification.
But to give it a present day application, complete with out-of-context other prophecies from other parts of the Bible, having no connection whatever is again cultic. Personally, I would avoid such a perilous and uncertain understanding. One never knows.... one may begin to see oneself in Scripture, as Russell, Rutherford, Franz and Armstrong did.
And look where it got them
Cheers