Editor's note: Sen. Ted Cruz is a Republican representing Texas. The opinions expressed in this commentary are his.
(CNN) -- This week, as we mark the 13th anniversary of horrific attacks on our home soil, Americans should have no illusions about the terrorists who have repeatedly declared their intent to strike America again.
We know the threat of the vicious terrorist organization known as ISIS has concerned the intelligence community for more than a year. And the group's atrocities have been well-documented since it began attacking northern Iraq, and it is deeply concerning that it has taken President Barack Obama so long to develop any kind of strategy to address these increasingly powerful terrorists who have now gruesomely killed two American journalists before the world stage.
On Wednesday evening, the President will finally share with the American people his "game plan," as he calls it, to combat ISIS. It is my hope that he will propose a clear plan, consistent with the Constitution, to keep Americans safe, and that it is not laden with impractical contingencies, such as resolving the Syrian civil war, reaching political reconciliation in Iraq or achieving "consensus" in the international community.
There are three specific steps that should be taken.
First and foremost, Washington should resolve to make border security a top priority finally, rather than an afterthought, of this plan in light of concerns about potential ISIS activities on our southern border, cited in a Texas Department of Public Safety bulletin reported by Fox News. As long as our border isn't secure, the government is making it far too easy for terrorists to infiltrate our nation.
Second, Congress should make fighting for or supporting ISIS an affirmative renunciation of American citizenship. Numerous Americans have joined ISIS along with hundreds of others from the European Union.
We know that some of them are trying to return to their countries of origin to carry out terrorist attacks. How do we know that? It's already been attempted. On May 24, a suspected French jihadist with possible ISIS ties traveled to Belgium, where he is accused of attacking innocent visitors at the Jewish Museum of Belgium in Brussels and slaughtering four people -- and it was reported earlier this week that he allegedly had been plotting a larger attack on Paris on Bastille Day. In August, an accused ISIS sympathizer, Donald Ray Morgan, was arrested at John F. Kennedy International Airport in New York trying to re-enter the United States.
On Monday I filed the Expatriate Terrorist Act of 2014, which would amend the existing statute governing renunciation of U.S. citizenship to include fighting for a hostile foreign government or foreign terrorist organization as an affirmative renunciation of citizenship. By fighting for ISIS, U.S. citizens have expressed their desire to become citizens of the terrorist group, which calls itself the Islamic State. We should not permit them to return to America, with a U.S. passport, to carry out acts of terror at home.
It is my hope that this legislation will attract bipartisan support, and will bring Washington together with one united voice in support of keeping Americans safe from ISIS acts of terror.
Third, we should do everything possible to make ISIS understand there are serious ramifications for threatening to attack the United States and for killing American civilians. While damaging ISIS' financial assets is certainly a part of this action, because of the very nature of ISIS, the response must be principally military.
We should concentrate on a coordinated and overwhelming air campaign to destroy the capability of ISIS to carry out terrorist attacks on the United States.
The President's previously stated goal -- to "shrink" ISIS' "sphere of influence" until it is a "manageable problem" -- is not encouraging. The objective should not be to make ISIS "manageable"; the objective should be to protect the United States and to destroy the terrorists who have declared jihad on our nation.
The White House's suggested ways of countering ISIS have, so far, been naive and ineffective.
Now, faced with the growing threat of the group, Americans are being told Syria and Iran may suddenly be our friends, and ISIS is now our enemy. This is nonsense.
The enemy of our enemy is not always our friend.
Other possible objectives the White House is considering are equally worrisome. We must reject the notion that any U.S. action be contingent on political reconciliation between Sunnis and Shiites in Baghdad. The Sunnis and Shiites have been engaged in a sectarian civil war since 632. While we all wish the Iraqis success in their most recent attempt to form a government, it is the height of hubris and ignorance to make American national security contingent on the resolution of a 1,500-year-old religious conflict.
Likewise, any action we take to stop ISIS should not be contingent on any consensus from the so-called international community.
America is blessed to have good friends and allies who understand the threat of ISIS, and we welcome their support. Indeed, this is an opportunity to reverse the destructive policy of the last five years of reaching out and appeasing our enemies while giving our allies the cold shoulder. Instead, we should partner closely with our friends in the region who are already engaged in this fight, notably Israel, Jordan and the Kurds.
This mission must be led by the United States if it is to be done right, and we cannot make the assembling of a coalition a higher priority than the execution of our mission.
And, leading that mission requires a clear articulation of the mission. Finally, the President appears to have ruled out making any formal authorization request from Congress to take military action. This is wrong.
I ask the President to reconsider.
Only Congress has the authority to declare war. While our commander in chief has constitutional authority to respond to an imminent danger, Obama has not suggested that is the case. He is reportedly planning a mission that could last as long as three years and may require a range of actions.
Therefore, congressional authorization is required by the Constitution.
Making this formal request would provide the President with an opportunity to present the American people with a clearly defined military objective, tethered to national security, to protect our nation and to unite everyone in the mission to eradicate ISIS.