I hear you, but I don't think the theories are opposite to each other.
Let's take them one at a time. First, would you agree that angry rhetoric, intimidation and surveillance contributes to ISIS getting more recruits? If so, then it's a true statement, independent of the other statement.
Regarding the second, I'm not sure the word "soft" is warranted here, as it prejudges the question in advance. The question you seem to be asking is whether our current response to terrorists signals that the West is weak and thus does not provide sufficient disincentives to terrorists. When using the word terrorists, it seems that you are speaking about the people carrying out the acts. Those people generally are prepared to die - many are either suicide bombers, or make suicide-style attacks expecting to die. Thus, using tactics such as police surveillance of neighborhoods as Cruz proposed is unlikely to provide a disincentive at all. Heck, even jailing them for life will not, or taking 10 years to kill them as our current death penalty laws stand.
Now, I can try to steelman the second theory, and talk about the people behind the suicide bombers, those who incite them - so not terrorists themselves, but ideological leaders. Having police patrol Muslim neighborhoods will do nothing to deter ideological leaders, natch - they are the radical imams in mosques, the bloggers on the internet, etc. So my point still stands on Cruz's solution being, to say it mildly, unhelpful.
Can we do something about the radical imams? Sure! However, this is not a topic I chose to focus on in the article, and I haven't given it sufficient consideration to make a strong and clear statement about it. I'd welcome thoughts from LWs about what can be done.
Can we do something about the radical imams?
Put them in prison. Assassinate them. Discredit them. Make fun of them publicly. All of the above.
Trigger warning: politics is hard mode.
"How to you make America safer from terrorists" is the title of my op-ed published in Sun Sentinel, a very prominent newspaper in Florida, one of the most swingiest of the swing states in the US for the presidential election, and the one with the most votes. The maximum length of the op-ed was 450 words, and it was significantly edited by the editor, so it doesn't convey the full message I wanted with all the nuances, but such is life. My primary goal with the piece was to convey methods of thinking more rationally about politics, such as to use probabilistic thinking, evaluating the full consequences of our actions, and avoiding attention bias. I used the example of the proposal to police heavily Muslim neighborhoods as a case study. Hope this helps Floridians think more rationally and raises the sanity waterline regarding politics!
EDIT: To be totally clear, I used guesstimates for the numbers I suggested. Following Yvain/Scott Alexander's advice, I prefer to use guesstimates rather than vague statements.