The main decider on this topic may be the eventual outcome of the Iraq War.
If American interests were to come to fruition in Iraq and the Iraqi government became a thriving democratic government, supported by a vibrant world class economy.
Then the likelihood of another nation (not counting Iran and North Korea) rising to an equivalent stature (of military attention) as pre-war Iraq would be slim.
Should America "lose" the Iraq War, meaning that the United States withdraws all their troops from Iraqi soil without the confident establishment of a stable and friendly government, then the likelihood of another major military action by the United States would rise.
Now that America has asserted their interests in the Middle East, they will need to follow through to success in order to deter future renegade regimes from antagonizing the United States and its allies.
There is also the military factor to assess.
The military as it is now is trying to adjust to the new doctrines of severely limiting casualties, raising lethality, and creating more specialized units.
While these doctrines have been extremely effective in making sure 99+% of our GI's come home safe and (mostly) intact, they have also limited the scope of the United States military options at its current size.
In other words, if the United States were to take on another action of equivalent size and complexity to that of the Iraq War, it would need to plan on increasing its numbers ahead of time to deal with the unforeseen troop strain before it becomes an issue (as it has now).
All of this can be done, the question here is would the American public (ergo Congress) pay for this? Although frustrating, at this time, the answer to the original question is another question: is America going to "win" the Iraq War?One thing is for certain.
We still have yet to define victory in Iraq; the longer it takes us to "win" in Iraq the higher the likelihood that we will have to deal with a like circumstance in the future is.