President Ronald Reagan had a dream. Let's build a missile shield that will protect us from our enemy's nuclear missiles. In popular culture, we called it Star Wars and ever since, our country has been spending billions of dollars to try to create an anti-ballistic missile system.

Now, the Bush administration plans to deploy a national missile defense system in California and Alaska that has already cost $130 billion. This year, the Bush budget calls for spending yet another $10.2 billion.

But who is the enemy? If it's North Korea, diplomatic reassurance that we will not invade that country will work better than a still unproven missile system. If it's China, why have we given them "most-favored nation" trade status? If it's Iran, they do not have the nuclear material or the missiles with which to attack the United States. If it's al Qaeda, no missile shield will protect us from a dirty bomb, the dispersion of biological or chemical weapons or suicide bombers who decide to detonate themselves in our shopping malls.

But the real problem with the missile shield is that scientists say there is virtually no proof that we Americans have gotten anything for our billions of dollars. Nevertheless, President Bush is determined to get Star Wars up and running by Sept. 30, before the presidential election. Why? Probably because he wants to prove that, despite the disarray and scandal in Iraq, he is the leader who can protect our national security.

Scientists, however, have voiced great doubt that any part of Star Wars can work. In a May, 76-page, report titled "Technical Realities," the Union of Concerned Scientists found "no basis for believing the system will have any capability to defend against a real attack."

In addition, 49 retired senior military officers, including a former chairman of the Joint Chiefs of Staff, wrote an "Open Letter to the President" in March, asking Bush to postpone deployment of an untested and unproven ground-based missile shield. Instead, they want the president to use these billions to "accelerate programs to secure the multitude of facilities containing nuclear weapons and materials and to protect our ports and borders against terrorists who may attempt to smuggle weapons of mass destruction into the United States."

They have asked Bush to commit these billions of dollars to fortifying our nation's seaports and trains and other sites vulnerable to terrorists.

In addition to improving homeland security, think what California's share of these billions could buy. Money that's projected for ballistic missile defense in 2005, for example, could pay for 205,234 housing vouchers or health care for 413,584 uninsured adults or 21,569 elementary school teachers, or 6, 079 fire engines, or 163,534 Head Start placements or health care for 949,480 children.

Beyond spending precious taxpayer dollars, Star Wars has voided the 1972 Anti-Ballistic Missile treaty and is likely to ignite an arms race with other countries -- perhaps China.

Nor is the missile shield completely defensive. As many critics have noted, the technology needed to make a ballistic-missile system work perfectly also creates the ability to build offensive space-based weapons, which would violate the Outer Space Treaty of 1967.

Late in the fall of 2001, Secretary of Defense Donald Rumsfeld delivered to Congress a report from a task force he chaired. It was called "Vision 2020" and described how the United States could use space-based weapons to dominate the world. Such military dominance, however, will only intensify fear and resentment of our nation and likely result in even more terrorist attacks. Memo to the President: You can't win an urban battle in Fallujah with space- based weapons.

Star Wars, like the war in Iraq, is a military choice, not a necessity. We don't need more weapons to secure our future. What we need are solutions to the ethnic and religious clashes and political and economic inequities that divide the people on this planet.