It is popular for many to say that we were foolish to destroy Saddam's regime because he was a counter-weight to Iran and now Iran can attempt to influence Iraq. A smaller chorus says the same about the similar situation in Afghanistan.
It is true that Iran attempts to influence Iraq and Afghanistan after the virulently anti-Shia Iran governments of the Taliban and Saddam were defeated:
Many Iranians consider Iraq and Afghanistan as part of “greater Iran” because both those areas were once part of an Iranian empire (along with most of Pakistan and a large chunk of Central Asia). Since the violently anti-Shia (and anti-Iran) governments were removed from Afghanistan (in 2001) and Iraq (in 2003) Iran has expanded its influence there at the government and ground level. Diplomatic relations were improved and much charity work was undertaken. But the charity came with strings; recipients were restricted to those who were pro-Iran, or willing to be. This made it much easier to recruit spies and terrorists, or just mobilize a large pro-Iran (or anti-American) demonstration. Iran has always preferred the long game and knows that if it keeps at it, eventually Iraq and Afghanistan will become, if not part of Iran, than very cooperative with Iran.
This is true as far as it goes. Of course Iran will try to bend events to their benefit. But this charge of gifting Iran neglects that it was in our interest to defeat both the Saddam and Taliban regimes.
And it neglects that destroying these regimes is only a gift to Iran if we don't resist Iran now and in the future.
Remember, it was no gift to Stalin to destroy Hitler's Germany because we stayed in Europe and defended it with NATO through a long Cold War. All through the post-World War II era, the Soviets attempted to open their "gift" with support for Euro-communist parties and through external military pressure. There is no way the Soviet Union could have attempted this had we not joined with them in destroying Nazism and Fascism in Europe.
Yet the gift blew up in Moscow's face however, in 1989 and worse in 1991. All because we continued to bend events to our benefit. And it worked.
Which is why I've been so upset that we failed to come to an agreement with Iraq last year to keep combat forces in Iraq to resist the Iranians and build up Iraqi ability to resist Iranian influence (and to build domestic rule of law).
Which is why I'm nervous about whether we'll really follow through with our intention of keeping combat forces in Afghanistan after 2014 to help Afghans resist Iranian influence (and Taliban resistance) and help Afghans develop the ability to stand on their own.
The real gift to Iran isn't destroying enemies we both wanted to defeat. The real gift is walking away and letting Iran exploit the mutually beneficial result of destroying two evil regimes that waged war on us.
If we stay and fight for our interests, things could blow up for Iran, too, despite their grand hopes to expand their empire.