Horrific terrorist carnage in Paris has refocused Washington's attention on the Islamic State (IS) group and its ambition to strike within the United States.
Amid a global outpouring of grief and sympathy for France, are reminder the top Democrat on the House Intelligence Committee,that America is also a target.
"We cannot allow ISIS to have this sanctuary in Syria and Iraq from which to plan and direct attacks against us," Schiff added.
White House officials are seeking to reassure the American public.
"There is not a specific, credible threat to the homeland at this time, but we are going to be very vigilant," said President Barack Obama's deputy national security adviser, Ben Rhodes, also on This Week.
Of particular concern: the Paris attacks demonstrated that terrorists can plan, coordinate and execute bloody plots with little or no Internet chatter or other communication that may tip off intelligence agencies. If Islamic State caught France by surprise, could it do the same to the United States?
"The reality is: even the best intelligence will not stop a determined enemy that adapts to our defenses, and ISIS has adapted," said Schiff.
Refugee dilemma
Reports that one of the Paris attackers may have been a Syrian asylum seeker will bring increased scrutiny of the Obama administration's pledge to accept 10,000 refugees from Syria.
For months, Republican presidential contenders have blasted the administration's campaign against IS as woefully inadequate. Now, they are disputing White House assurances that Syrians granted U.S. asylum will be subjected to thorough screening and vetting.
"You have a thousand people come in, and 999 are just poor people fleeing oppression and violence. But one of them is an ISIS fighter. If that is the case, then you have a problem, and there is no way to vet that out," said Republican Senator Marco Rubio. "You cannot pick up the phone and call Syria."
At Saturday's debate among Democratic presidential hopefuls, Hillary Clinton pointedly disagreed with Obama's assertion last week that the Islamic State group has been contained.
White House officials say the president was referring to the territory controlled by IS in Iraq and Syria, not the terrorist threat posed by the group.
Vocabulary
sanctuary:(圣经)圣幕,圣堂
vigilant:警惕的
asylum:庇护;收容所
assertion:断言,声明
国内英语资讯:Chinas economy steady, outlook positive: think tank
国内英语资讯:Chinese national flag raised in Chicago
国内英语资讯:China to deepen VAT reform
国内英语资讯:Chinese naval escort fleet concludes visit to Denmark
体坛英语资讯:Miralem Pjanic to miss the match against Belgium
国内英语资讯:New China-Europe rail-sea cargo route opens
国际英语资讯:Myanmar nationals start to enjoy visa exemption for visiting India
长假去哪儿?CNN盘点中国最美的四个水乡
假期阅读推荐:助你迈向成功的十本书
奈飞的一封“威胁信”刷爆外网,风格很小清新
Why Pandas Are Dying Out 为什么熊猫面临灭绝
专家:宽脸女人是天生赢家
美国将大幅度减少难民接收人数
体坛英语资讯:Valencia striker Rodrigo into Spain squad
盐和糖的保质期,远比你想象的长
9月资讯热词汇总[1]
体坛英语资讯:Former Dortmund coach Tuchel expected to take over Bayern Munich
中国高校富豪校友排行榜 清华最盛产亿万富豪
国内英语资讯:Chinese human rights delegation visits?Britain
国际英语资讯:Chinas current account surplus remains in reasonable range
专家:宽脸女人是天生赢家
体坛英语资讯:Canada clinch pole position in first qualifier at FEI Nations Cup jumping final
假期阅读推荐:助你迈向成功的十本书
体坛英语资讯:Kenyas athletics chiefs alter calendar to accommodate international events
国际英语资讯:Somali forces kill 18 Al-Shabaab militants in army base attack
国内英语资讯:Xi calls for profound understanding of Marxism
国内英语资讯:China to further cut red tape for better business environment
对象从不带你见家人朋友?你要多想想了!
境外商家向中国游客推出“超国民待遇”
国内英语资讯:China holds reception to celebrate National Day