For seven years we’ve all watched as America’s global leadership has declined and radical Islamic terrorism spread around the world. The explosion of this global ideology of violent extremism is only accelerating, and innocent men, women and children are paying the price for our ineffective action and failure to lead. 
What will it take for America’s leaders to wake up to the true nature of radical Islamic terrorism? Even after horrifying attacks in San Bernardino, Calif. President Obama refuses to acknowledge this threat for what it is: a radical ideology that seeks to violently impose Islam on others and supplant existing cultures and duly constituted governments around the world. We cannot defeat the Islamic State and other brands of radical Islamic terrorism until we confront this truth.
Instead, we have an ineffectual strategy without direction and without dedication. While bombs fall around Raqqa, Syria, enclaves of the would-be Islamic State caliphate have sprung up in Libya and other North African nations, as well as the Gaza strip and even Pakistan. Unless we act now, these ISIS loyalists will only entrench their positions as they work to meet each other in the middle. 
These are not just the ambitions of faraway mad men. Around the world people are working to advance this ideology -- not just in the Middle East, but here in America as well.
Whether through violent attacks like San Bernardino or the shooting of a police officer in Philadelphia, or through social “lawfare” tactics designed to silence criticism and advance the goal of imposing sharia, Islamic jihad has already reached our shores. For example, the Council of American Islamic Relations (CAIR) has been operating in the U.S. for more than 20 years. Although CAIR claims to represent peaceful Muslims in civil rights issues, its history ties directly to the terrorist organizations Muslim Brotherhood and Hamas. CAIR was named an unindicted co-conspirator in the Holy Land Foundation’s funding of terrorist attacks, several prominent members and founders have been incarcerated or deported for fraud and terrorism charges, and the countries of Egypt, Saudi Arabia and the United Arab Emirates have designated it a terrorist organization.
"As President I will declare war on the Islamic State . . ."
Most disturbing of all is the revelation during the Holy Land trial of a strategic document that called on members to conduct a ‘civilizational jihad’ to impose sharia law in the United States. This is not representative of all Muslim Americans, but rather of the terrorist organizations to which some are tied. We must fight this radical Islamic ideology wherever we find it, and by every means at our disposal. We must destroy terrorist movements like ISIS around the world while countering radical Islamic ideology here in the United States. No group can subjugate the U.S. Constitution to their will.
Recognizing the complex nature of this threat, I have put forward a plan to address radical Islamic terrorism, from ISIS fighters in Syria and Iraq to even non-violent jihad in the U.S. and elsewhere. Winning this fight will not be easy, but if ‘We the People’ unite behind the cause of freedom and American values, I know that we will prevail. This is hardly the first time the United States has been threatened by radical ideologies. Just as with Nazism and Soviet communism, the American people will prove too resilient to be defeated by expansionist and oppressive regimes like ISIS.
As President I will declare war on the Islamic State, taking back the territory through which it claims legitimacy. I will destroy the means by which it gains revenue and cut off the supply routes on which it relies, and I will work with regional partners and local forces -- including displaced Syrian men -- to take back that country from the jihadists. At the same time I will work with allies and partners in Europe and Northern Africa to halt the advance of the Islamic State in the Maghreb and turn back the growing tide of radical Islam across the continent. This movement is global, and our efforts must match it in scale and intensity.
This fight extends far beyond the illegitimate borders of the Islamic State and the soldiers they have recruited. My plan will leverage every American strength -- diplomatic, economic, political and cultural -- to combat radicalization and ensure that no country provides safe harbor for terrorism.
In the U.S., I will work tirelessly to defend our way of life from those who wish to destroy it. That means not only investigating groups like CAIR, but securing our borders to ensure that terrorists do not have a pathway into the homeland. Unlike President Obama, I will not allow a stream of poorly vetted people from Syria to come to the U.S. On the contrary, I will establish refugee safe zones in Syria and neighboring countries, so that refugees are provided for, but are also ready to return home when it is safe for them to do so.  
A president’s most solemn vow is to protect the people, whose country they have entrusted to him. This plan is my promise to uphold America’s security to my utmost, confronting our worst threats head on. Radical Islamic terrorism is the greatest threat we face today. But with the support of the American people, there is no challenge too great for us to overcome. 
Dr. Ben Carson is a retired pediatric neurosurgeon and Republican candidate for President.

Ben Carson, M.D. is Professor Emeritus of Neurosurgery at Johns Hopkins University and a Fox News contributor. He is author of "America the Beautiful: What Made This Nation Great" (Zondervan 2012).